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OL Science| Biology Seminar 1| Reproduction and Inheritance — Transcript

by Chirath Easwarage · 21,539 words · 3,803 segments · language en · Watch on YouTube

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0:12Okay. Uh the tudes are available in all
0:16the in the groups. Okay. So if you are
0:21in the group uh
0:25you should be able to access. I'll send
0:27right now to the Zoom chat as well.
0:30Okay. I'll be sending the two PDFs to
0:33the Zoom chat as well. Okay.
0:50You can access them from the Zoom chat.
1:08Okay. Uh don't worry about the group if
1:10you are not in the group right now.
1:13Right. Uh if you don't
1:18Yeah. We'll see. So today's plan is
1:21Right. Okay. We'll start. Huh. Anyone
1:26who's having any connection issue, you
1:28all can hear me and see me very clearly,
1:30right? Any issues, please quickly let me
1:33know. Okay? So, please keep the chat
1:39uh let's say
1:41without any spam. Don't spam the chat
1:44because it's a learning environment.
1:47Okay? Otherwise, I would have to remove
1:49the permissions to chat. Okay? Otherwise
1:51uh
1:53uh the opportunity for you to be
1:55interactive would be lost right so I'll
1:59enable chat option when we are having a
2:01break but otherwise I'll uh may be
2:06I might have to sort of remove the chat
2:08but anyway it's all right it's done as a
2:12free seminar so anyone who re require
2:17who has a requirement to get this
2:19covered before you go to the exam
2:21I'm doing this for you. Okay. So, small
2:24introduction. I'm Chiratish. So, I am
2:26doing A level English medium biology,
2:29right? And I'm a medical student.
2:31Actually, I'm almost about to graduate,
2:34right? Uh so, I have Alevel biology
2:38teaching experience for the past four to
2:40five years. I did my O levels in 2016,
2:44so almost 10 years ago. But the exact
2:47same syllabus, right? And you know a
2:51level biology is just the next step that
2:56you have to tackle. Of course, if you're
2:58doing A level biology,
3:00then you have to you can progress to
3:02biology science, right? Science level
3:07science.
3:09It's a tough subject, right? But anyway,
3:12O levels
3:15is a what we call as a bar exam.
3:20It's not competitive. You only have to
3:24pass all levels, right?
3:28You can get 9 years of course that's a
3:30very good achievement
3:32but it's what we call as a
3:36bar exam
3:39let's have a small introduction right so
3:41we about we'll start the seminar proper
3:44in a with the
3:47right so we can say your levels right
3:52it's a bar exam I'm not wasting your
3:55time on just sort of comparing it. You
3:58have to pass it to do what? To progress
4:02to A levels. Yeah, that's what you have
4:04to do. You have to pass it to move on to
4:06A levels. But your A levels
4:11is what? It's a competitive exam.
4:18It's competitive. Why? What are you
4:20competing for? What are you competing
4:22for?
4:24you are competing to get to university.
4:28I mean it's a qualification that you so
4:31all levels is a qualification as well
4:32but depending on your rank you are going
4:35to be ranked
4:37in your A levels according to a Z score
4:41according to EZ score
4:46there are rankers you know all of you if
4:49you have a positive ED score you're
4:51going to get a island rank island
4:55if you're applying for a state
4:56university medicine, engineering, then
4:59uh molecular biology, dentistry,
5:02veterinary science, computer science,
5:04right? All the other applied sciences,
5:07everything, anything that you are going
5:08to do will depend on this. It's a
5:11competitive exam,
5:14right? So what you have to do is in the
5:19coming two months
5:23levels
5:27right but in all levels you are
5:30developing the skills
5:34right and
5:37I am doing I'm not going
5:41I want to have an exposure
5:52That's why I'm doing this,
5:54right?
6:07Seminars from my side itself. All right.
6:10And I already told you
6:17right
6:31even I was right even I found the level
6:34biology parts very boring. Why is that?
6:38Because it's a theoryical subject just
6:40theory theory theory if you know the
6:42theory you can get marks right so you
6:46will think it's all about memorization
6:49memorization if you can memorize you can
6:53get the max
6:57but most of us 99% of us don't have a
7:00photographic memory
7:05every word
7:07Right? So because of that it's important
7:10that you find ways
7:14to actively learn by actively with
7:17Understand?
7:44It's fine. Right. Within two weeks you
7:47can let go of biology. But others who
7:49are going to do bio for your levels
7:53start practicing how to start memorizing
7:57how to study theoretical subjects.
7:59Right?
8:01So
8:03biology memorization subject
8:08why is it beneficial?
8:15because that's the let's say the most
8:17practical way right
8:24chemistry
8:30but if you come to bio
8:32it's just facts it's facts
8:36facts shortterm memory
8:43that's also a good method
8:56first class.
9:00So
9:03one of my targets with this seminar
9:06series is actually to help you with do
9:08that also shortterm memory
9:17one of the targets. Okay. So what are my
9:19targets? I want to help you master the
9:23biology parts in your science syllabus
9:26in a short period of time. Take it to a
9:28short-term memory. examin
9:31me. Okay. Then I as a A level
9:38teacher I want to get an experience with
9:41O level teaching as well. All right. So
9:44that's what I'm doing from my side.
9:46Okay. So with that we'll get to today's
9:52parts. Do you have any any questions
9:54that you want to ask?
9:56Please cover all biopaths. I'll
10:00try my best right but let's for today
10:03let's cover today's objectives let's
10:06cover today's objectives afterwards keep
10:09in touch
10:12as time permits we I'll see what I can
10:15do okay so today just focus with the
10:18goals for today right focus okay anyone
10:23who can't understand a word of single
10:25anything
10:27yeah of course I'm going I'm giving you
10:29recording. Yes,
10:29>> me sir.
10:30>> I'm giving you recording. Yes.
10:33And next week there will be a YouTube
10:35live, right? Because I don't have my
10:37technical person today to uh arrange the
10:40YouTube live. So
10:43next week there's going to be a YouTube
10:44live. And yes, of course, I'll give you
10:46the recording. No issue. Cannot
10:49understand singular. I'm repeating
10:51everything in English as well. Whatever
10:52I say in sing.
10:56Okay. Whatever I say in single I'm going
10:58to repeat in English. Okay.
11:00Okay. Right.
11:03Okay.
11:07No issue. Right. Okay.
11:11What do you have? What do you need to
11:13have? Take out your textbooks. Grade 10
11:16science text.
11:21For the final time you're going to learn
11:24the syllabus, the textbook from a
11:27teacher. Think of it like that. From
11:30this day onwards, it's going to be you.
11:31It's your self-study.
11:34Your self-studying is what is coming in
11:36the future.
11:39Textbook. You are going to be following
11:41with the teacher. Okay? So, take out
11:44your textbook. If you have the PDF,
11:46open it as well. But I'm going to open
11:48the PDF in my screen as well. So don't
11:51worry too much. The PDFs are available
11:53in the
11:55zoom chat and in the groups. Okay. And
11:58uh if you have any doubts, send messages
12:01to the zoom chat
12:03as a uh public message. Okay.
12:09Okay.
12:15So I I thought of starting with uh the
12:17reproduction part because you know if
12:19you take the past papers
12:24the weight of questions
12:26from these parts and also
12:33right I did a small research what are
12:35the most difficult
12:37grade
12:39it's reproduction particularly the
12:41female reproductive system then the
12:43genetics part when it comes to grade 11
12:46it's the body systems and also biosphere
12:49matratiaga
12:50so that's what my focus is going to be
12:54uh on the second seminar right I'll try
12:58my best to do another seminar but
13:01let's see okay so
13:05right let's move on okay I'm going to
13:08start with uh the introduction to
13:11reproduction okay so this is the tude
13:13that you have right I'll introduce the
13:15to there are some blank spaces right
13:18blank spaces
13:20right that is for you to fill right that
13:24is for you to fill there are blank
13:26spaces
13:28that is for you to use as a workbook
13:33okay fill in the blanks
13:36while you are listening or while you're
13:38watching the recording you are allowed
13:39to watch the recording right session you
13:42can watch the recording
13:43and uh
13:46get into your sort of if you didn't
13:47understand anything or if you missed
13:49anything you can watch the recording. So
13:52I have included some diagrams right some
13:56diagrams so that it's easy for me to
13:58explain and it's
14:01there's no use in giving you exact
14:04textbook back to you. So that's why I
14:07try to include a large let's say
14:10comparatively high number of uh
14:12diagrams. Okay. So
14:17this is the reproduction to you might
14:18have gone through it a bit right
14:23because I'm going to cover this whole
14:25section. Okay.
14:29And uh so this is the
14:32reproduction to I'm not going to right.
14:34So then uh afterwards we'll start on the
14:38inheritance the genetics right I'm going
14:41to nicely explain to you the mandelian
14:44genetics and also
14:51all right uh with some nice diagrams I'm
14:54going to explain the mandelian genetics
14:56and also some of the difficult concepts
14:58such as this uh gener linkage and uh
15:04also also sex determination and uh yeah
15:08and some of the inherited disorders sex
15:10link disorders blah blah
15:14okay and afterwards I'm going to discuss
15:16some of the most recent past paper
15:18questions okay
15:23right reproduction quickly come to the
15:26reproduction to okay
15:33So in your textbooks right in your
15:37textbooks
15:39classes teach right so I'm going to use
15:41the same methods
15:44what I use is there's a textbook called
15:47the biology resource book and I'm going
15:50I give my own to right so my students
15:54are supposed to while they are going
15:56through the textbook they are supposed
15:58to work on the
16:02class
16:04how I do my teaching, right? Okay.
16:09Reproduction in your textbook. Grade 10
16:12textbook, right? Grade 10 textbook.
16:15Okay. Grade 10 textbook
16:18page number 27.
16:20Okay. Grade 10. Page number 27. Any
16:23issues?
16:25N all of you can clearly hear and see.
16:30You said
16:44right.
16:49So reproduction what is the definitions
16:53are
16:55really important right? So basically
17:00process that gives rise to a new
17:01generation. Process gives rise to a new
17:04generation
17:07from an existing generation. Right? This
17:10existing generation what do we call
17:16parental generation right? We call it
17:19the parental generation. Right? Parents
17:22and who is the new offspring I mean
17:25right? What is the new generation
17:26called? We call them offspring.
17:30Offspring,
17:32right? So parents are producing
17:34offspring. That is how reproduction
17:37works. Right? If you take
17:39characteristics of living organisms
17:42define what the living organism, there
17:44are some words that we use. What are the
17:47things done by only living organisms?
17:50They grow, they develop, they reproduce,
17:53they adapt. Okay, they have metabolism
17:56reactions happening inside. One of the
17:59most defining features of a living
18:02organism is reproduction,
18:04right? Life must go on, right? Life.
18:08So to do that in the living world, you
18:11have two ways.
18:13Let's focus on the asexual reproduction,
18:16right?
18:18So reproduction by occurs by spores or
18:22vegetative parts of a mature organism.
18:24Mature organism this is the parent.
18:27All right. So spores or vegetative
18:30parts.
18:32These mainly refer to mainly plants
18:37produce spores and also fungus. Fungi
18:40produce spores.
18:42Okay. Then vegetative parts can be seen
18:46in animals
18:49and also plants
18:52asexually reproducing animals.
18:56Okay.
18:57So can anyone tell me in asexual
19:00reproduction what is the cell division?
19:03What is the cell division?
19:06Meiosis does not occur. Can anyone tell
19:08me then cell division? What is the cell
19:11division happening in asexual
19:13reproduction?
19:14>> Mitosis.
19:15>> If it is not meiosis, then what is it?
19:19>> Mitosis.
19:19>> Yes, it's mitosis,
19:22right? So, it's mitosis happening.
19:27Okay. So, mitosis happening means what?
19:30What is mitosis? It's exactly photocopy.
19:35Okay. No changes. No changes.
19:40That's not exactly copying. So mitosis
19:45doesn't allow anything else to happen.
19:49There is something additional happening
19:53then there's something wrong with the
19:54muses
19:57mutations.
20:01We can get mutations
20:05right
20:08but
20:10mutations when the mitosis goes wrong.
20:14So they are more or less like the
20:16maternal
20:20asexual reproduction we usually call the
20:22parent
20:24maternal mother.
20:27There is no production of gametes.
20:30What are the two types of gametes that
20:32you have?
20:34If it's a sexually reproducing organism,
20:38right?
20:40If it's a sexually reproducing organism,
20:43what are the two types of gametes? You
20:45have usually eggs,
20:49sperms,
20:55egg, it's usually bigger. The egg is
20:58usually bigger. And the sperm is usually
21:03smaller and usually is able to move is
21:07mortiles
21:11right gamts are not produced in asexual
21:14reproduction
21:17right new species are not produced
21:19because why it's a photocopy it's a
21:20photocopy you can't do anything new you
21:23can't do anything new large number of
21:25offspring can be produced yes again it's
21:28a photocopy Right. You can print a large
21:30number of copies,
21:32right? In a small amount of time,
21:36right? See new primitive plants and
21:38animals. Yes. Because you will see new
21:42species. We need changes. We need
21:45changes.
21:48Changes otherwise you can't progress as
21:51a species. Right? Sexual reproduction.
21:57There are two partners involved. Who are
22:00the two partners? There's a male and a
22:02female.
22:04They produce gametes. They combine.
22:08Okay. The male and female gametes
22:10combine and results in a
22:15one cell. That one cell is called what?
22:18The first cell. We are going to talk
22:20about that in human development. Right?
22:23Zygote. Zygote is going to divide,
22:24divide, divide, divide and give rise to
22:26a
22:28big new organism.
22:31Structures that are adapted for sexual
22:33reproduction can be found in
22:34evolutionary advanced organism. These
22:36are called what? Your sex organs. Sex
22:39organs,
22:41right? What are the organs developed for
22:44sexual reproduction? Those are sex
22:45organs. In plants, the structure that is
22:48especially formed for sexual
22:49reproduction is called what? Yes.
23:02What is the plant? I mean what is the
23:05flower? So what is the structure in
23:09plants that is specified or specialized
23:14for sexual reproduction?
23:18Oh yes.
23:22Flower,
23:25right? Flower.
23:32Right. In animals, there are male and
23:34female reproductive organs. Contribute
23:36two organisms which are referred to as
23:38right.
23:42You are the product of a sexual
23:44reproduction. So who are the people that
23:46were enrolled?
23:48Who are the people that were enrolled?
23:53Yes,
23:56that was the mother. Two organisms that
23:58are referred to as maternal and
24:02paternal.
24:05Okay. Gives rise to offspring which are
24:07mixed characters. Right.
24:12Right. skin tone right skin tone.
24:17So you are mixed product of your mother
24:20and father. Gamits are produced by meios
24:23is very very important.
24:27Okay. New species with better adaptation
24:30to the environment is produced. Right?
24:32So with sexual reproduction there is
24:36opportunity for the species to progress
24:40updates. Right? It's like updates coming
24:43to a new phone, right? So improvements
24:45improvements
24:47to survive better to survive better
24:51adaptation increase in the number of
24:53offspring is slow because right it's
24:55difficult to do sexual reproduction.
24:58It's difficult. What's the first thing
25:00that you need to have to do sexual
25:02reproduction?
25:05You need to have
25:07two organisms.
25:11You need to have a partner, right? So
25:14that's very difficult. Look at the human
25:16population,
25:17right? It's very difficult to do sexual
25:20reproduction. It's very difficult to do
25:22sexual reproduction, right? I won't go
25:25any further with that. Taggala these are
25:28all right. These are can be question in
25:29the structure they can ask you to
25:32compare asexual and sexual reproduction.
25:35Right? So we are jumping to the
25:36reproduction of man because fresh I'm
25:39going I need to cover this right while
25:41we are fresh I need to cover the human
25:44reproduction part okay
25:48so in in your textbook right in your
25:52textbooks
25:56come to page number
26:00you should know this better okay
26:02reproduction of man page number 47 Okay.
26:05So always while you are in this seminar
26:08this is the last time you are learning
26:10this with a teacher. Okay. Before the
26:12exam probably. Okay. Otherwise from this
26:16day onwards it's your you are self.
26:21Right.
26:24Okay. Right. So do it properly.
26:28Before we do reproduction we need to
26:31mature. Right. equipment we need to
26:34upgrade right we were born with
26:38let's say
26:40smaller primitive versions unlocked
26:43sorry locked versions of the equipment
26:46but you have to upgrade them modify them
26:48develop them make them bigger if you
26:49want to sexually reproduce so that
26:53happens during a stage of your life that
26:56means that you are
26:58transitioning from a child to the adult
27:02Okay, that happens in the adolescence,
27:06right?
27:07What is the definition
27:10sexual maturity or attaining
27:12adolescence? It is the puberty
27:15that's the definition of puberty. Okay,
27:19attaining the sexual maturity is called
27:22as attaining puberty, right? Puberty.
27:26So how do we know that someone is ready
27:29to do sexual reproduction? How do we
27:32know a human male or a female is ready
27:35to do sexual reproduction? How do we
27:37know? It's by looking at certain
27:40features, right? They are all secondary
27:43sexual characters. So
27:46we can see that that baby is either male
27:49or female. You can understand roughly
27:53right by what? by the small sexual
27:56organs. So those are primary sexual
27:59characteristics, right? There's nothing
28:01much else different other than the sort
28:04of external genitals, right?
28:08But once you are in the puberty, right,
28:11you are in the adolescent age, there can
28:13be some nice differences between male
28:15and female, right? Some girls, right? If
28:20you come to the female size, usually
28:22girls attend puberty earlier
28:26puberty grade
28:30the girls are much taller
28:35grade seven
28:38even
28:42but the girls are tall.
28:45So that's because see girls start to
28:47achieve puberty by 10.
28:5013
28:51right average.
28:54Right. Focus on the males. Boys first.
28:57What is the hormone responsible?
29:01What is the hormone? Main hormone
29:03responsible
29:05to convert a child to a man.
29:08Testosterone, right? Testosterone.
29:14It which is only one. There are so many
29:17other hormones but the main one is
29:18testosterone.
29:20Okay.
29:23What are the changes that you can see?
29:25I'll just uh show you this diagram,
29:28right? It's in your tubes. Uh this is a
29:31comparison of how with different ages
29:38the external appearances change, right?
29:42How the external genitalia change? How
29:45the pub I mean pubic hair pubic hair
29:49grow there are patterns right? If you
29:51take a male
29:53if you take a male something additional
29:56right if you take a male
30:00right
30:04sorry
30:07the hair grows like this. If you take a
30:11girl, the hair grows like this pubic
30:14hair, right?
30:18Okay. So, the external genital size
30:21increases in females.
30:24What can you see? The hips make hips are
30:28almost similar to boys, but with time
30:31the hips start to get wider. Why is
30:35that?
30:38Why is that? Because it's easier to
30:42bear the pregnancy
30:46with the wide. Yes. Very good. To bear
30:47the baby then memory glands start to
30:51develop, right? Memory glands start to
30:53develop, right? With age. Okay.
31:11they didn't get the first period like
31:13that. So when you are examining we can
31:16give a stage of puberty
31:21stage if that child is in the proper
31:26in which stage of puberty we can give a
31:29sort of a grade by looking at observing
31:32these changes. Boys mainly external
31:41right
31:45hair is going to come on almost
31:47everywhere. Face, chest, under armpits,
31:50genital areas of of course shoulders
31:54become wider, right? Shoulders become
31:56wider. Vshape,
31:59right? Upper body is wider.
32:04Lings enlarges. What is the larynx?
32:08Larynx is the upper part of your
32:10respiratory system. Upper part. Nose.
32:13Larx. Then you have the larynx.
32:18Okay. So larynx is where you have your
32:22vocal cords. Okay. If you want you can
32:24write down larynx. In the larynx you
32:27have your vocal cords.
32:31Okay.
32:34Therefore these vocal cords actually
32:36become thicker. Vocalord thick.
32:41So when air vibrates against those vocal
32:44cords, the voice sound produced is
32:47deeper.
32:49Bones and muscle grow faster and the
32:51growth is accelerated.
32:54Right? Genital start to grow larger
32:57obviously
32:59female. Right? Let me know if I'm going
33:01too fast. Okay, let me know if I'm going
33:04too fast. Females,
33:06we have two main hormones, but actually
33:10estrogen is the main uh responsible uh
33:13hormone.
33:16O estrogen,
33:19progesterone
33:24are the hormones responsible, right?
33:27Pubertal hair mainly girls it's in the
33:30armpits and the genital areas okay pubic
33:33region widens as I told you the pelvis
33:37memory gland start to grow we don't
33:39write memory glands
33:45right but inside the breast you have
33:47memory glands but also the breast gets
33:49bigger because of some fat deposition
33:51fats
33:53fat deposit you know
33:56in the hypodermis This hypodermis means
33:58below the skin. Below skin
34:05body becomes fat.
34:11Yeah. I mean anyway females have more
34:14body fat than males on average. Females
34:17body fat
34:20but fat.
34:23Okay. Bones and muscles. This is similar
34:26bones and muscles grow fast
34:29right
34:33starting of releasing of from ovaries
34:37menstruation starts right first bleeding
34:41right
34:43so this is secondary sexual
34:46characteristics of male and female
34:49right
34:51in the boys it's a bit late 13 to 16
34:54years in Girls is 10 to 14 years.
34:56Testosterone for males ostrogen
34:58progesterone for the girls.
35:01For boys the hair growth is actually
35:03greater. Face chest additionally hino
35:07right voice becomes deep. Shoulders
35:09become wide. Right. Testes start to
35:11produce sperms. Right? Testes. So
35:14ovaries are the female
35:17gonads and testes are the male gonads.
35:21Okay. Any questions? Any
35:27questions?
35:31Okay,
35:37you can clearly see the board and
35:39everything. Yes,
35:41reply.
35:47Okay. Okay. Moving on.
35:56reproductive system. Okay.
36:00I'll uh
36:02use my
36:04software a little bit to show you bit of
36:07a 3D idea. Right.
36:16Right.
36:29It's important that you have a nice 3D
36:32idea before we go. So you might remember
36:35this from my yesterday video. Okay.
36:38Right.
36:39Reproduction system.
36:41Okay.
36:46So
36:48right let's remove the skin
36:56right if you remove the skin you will be
36:58able to see nicely the male reproductive
37:01system okay it's mainly it's a very
37:04simple system the male reproductive
37:06system is very very simple right because
37:09why it's designed to do only two things
37:12so actually The male reproductive system
37:14is very closely associated with the
37:16urinary system. Pick you know
37:18eurogenital system. Okay. So actually
37:21the male reproductive organs male sex
37:24organs are
37:27specialized to do only two things what
37:30to produce sperm I mean yes to produce
37:33sperm to release sperm and that's the
37:35same thing and also to pass urine with
37:37the specializ
37:40okay nothing else
37:42right that's why it's very simple very
37:45very simple
37:49Right.
37:52So, right, these are the bones in the
37:56sort of that pelvic area. Okay.
38:00Let's remove the bones as well.
38:06Then we are left with just uh the male
38:09reproductive system. Okay.
38:16Coverings. We can remove some of these
38:18coverings.
38:20Then we are able to see the main
38:24let's say
38:26the main role of the male reproductive
38:28system not the penis this one the
38:30testice okay testice testice is the main
38:34role where sperms are produced and where
38:38testosterone is produced testice this is
38:41the testice where the sperms and the
38:43testosterone is produced. So sperms are
38:46produced in the testice.
38:49You can see the cross-section of the
38:52testice where you have the testicular
38:54lobules. I'll explain lobules of the
38:57testice and inside you have the
38:59seminifpherous tubules right on the
39:02tightly packed coil of seminifpherous
39:04tubules. That's where the sperms are
39:06born, right? Sperms in those
39:09seminifpherous tubules and the sperms go
39:12into this epidmus. Epidmis.
39:17So I like to call epidmus is like a
39:21training camp. Training camp and a
39:23hostel and a hostel for the sperms.
39:26Sperms mature.
39:28sperms mature in the epidmus and also
39:31the sperms are
39:33stored in the epidmus.
39:36Then from the epidmus there's a tube
39:39called the vast difference that is this
39:44tube blue color may right that blue
39:46color tube v difference that is going to
39:48transport the sperm.
39:54What is this big structure? This is big
39:55structure. Anyone?
40:00>> That is big structure. I'll make it
40:02blue. Yes.
40:04Who is this big structure?
40:06>> Prostrate gland.
40:09>> Yeah, it's a bladder,
40:12right? Bladder.
40:14So, as I told you, the male reproductive
40:17system
40:18is designed to urinate and produce.
40:22Okay. Right. So we'll keep the bladder
40:24home. Then there are some other
40:26additional. So
40:29from so some of the bones are remaining.
40:32Okay remove. So the bladder receives
40:35what? Urine from where? The kidneys.
40:39Okay. Bladder receives urine from the
40:40two kidneys. What are these two tubes
40:42that are bringing urine? Anyone?
40:46>> Uritus.
40:48>> These are called urus, right? Uritus.
40:51Uritus bring urine to the bladder and
40:54the bladder stores the urine. Okay.
40:57Then we have in the male reproductive
41:00system there are some accessory glands.
41:02We call them accessory glands that are
41:05necessary for the sperms to survive.
41:09Right? The sperms
41:12by just releasing the sperm to the
41:14outside we can't expect them to survive.
41:16They're not going to survive. They need
41:18some nutrition and they need a transport
41:21medium. That transport medium is going
41:23to be produced by some glands. First one
41:27is here that is called the
41:30yes seinal vesicle. There are two seinal
41:34vesicles. This one, this is the other
41:37seminal vesicles. Okay.
41:41This big structure is called what? That
41:45is your prostate gland.
41:47in prostate gland, right? So the
41:51prostate gland is this
41:54and prostate gland. Yeah, let's keep the
41:57prostate gland for now. So then we have
42:00the beginning of the or the base of the
42:02penis, right? Penis,
42:05right? Uh so penis goes like this and
42:09opens to the outside
42:11here.
42:13So what is the tube that is running
42:15through the penis? penis.
42:18What is the tube that is running through
42:19the penis?
42:21To see that tube, we need to take some
42:23nice cross-section. So, let's take a
42:26look inside the prostate.
42:28Let's cut the prostate gland and take a
42:31look inside. Right. Let's cut the
42:34bladder also. Right
42:38on. So, this is the interior of the
42:40bladder. This is the interior of the
42:41bladder.
42:45This is the interior of the bladder. So
42:47who is this coming out of the bladder?
42:50Who is this coming out of the bladder?
42:52There is the final part or let's say
42:55final pathway for the urine to go out of
42:57the body. Urine
43:00through this tube that is called the
43:02urethra.
43:03Urethra right
43:08urethra. We call it prostatic urethra.
43:10We don't need those. Right? Just this is
43:13the urethra. Now you can see the urethra
43:15is entering into the penis. Urethra is
43:18entering into the penis.
43:23Who are these two people?
43:27We call them koopus glands. Koopus or
43:29balbo urethral glands. Koopus glands or
43:33balbo urethral glands. Right? So the
43:37seinal vesicles add some secretions.
43:44Semen seinal vesicles add some
43:46secretions. Then the prostate gland add
43:48some secretions. Then these bulb
43:51urethral or cus glands add some
43:53secretions.
43:54All of them are going to go inside the
43:56penis. So this is the penis. I have
44:00removed the part of the penis. This is
44:02the urethra. Right? Blue color urethra.
44:06That is going to take what? Sperm or
44:10urine.
44:12Right. Sperm and urine come out of the
44:15same opening. Opening sperm and urine
44:18coming out. Okay.
44:22Uritra.
44:24Same opening.
44:26All clear. So if you are interested,
44:30I'll add some of the other systems.
44:32Right.
44:34I'll add uh the rest of the
44:39digestive sort of uh I can add the
44:42digestive system to this
44:45right. If I add the digestive system,
44:49this is the anus, right? This is the
44:51anus.
44:55I'm opening the anus, right?
44:59Then some of the digestive system also
45:01there. But I I'll be doing the systems.
45:03I'll be doing systems next week. Maybe
45:05there digestive system. This is the
45:07small intestine. On the two sides, you
45:10have the large intestine.
45:12Okay. stomach.
45:15Then you have the esophagus.
45:21Right.
45:24Okay. Clear about the male reproductive
45:26system. 3D.
45:30Okay. Right.
45:41Activities
45:43of the male reproductive system.
45:45Activities of the male reproductive
45:46system. Most importantly, it has to
45:49produce the sperm. Sperm is the vehicle.
45:52Sperm is the vehicle that takes your
45:54father's information to you to make you
45:59production of sperm. Ejection of sperm
46:01into the male reproductive system. The
46:03sperm,
46:05right?
46:07Sperm
46:09plus secretions
46:14from these glands
46:18together is called what?
46:22Semen not semen.
46:27semen liquid you produce a fluid that
46:30will be pushed spread into the into the
46:34female reproductive system and also the
46:36production of testosterone which makes
46:39men
46:48How is sperm produced? If I draw a test
46:51like this, if I draw a test like this,
46:55you have the epidmus.
46:58It's like a testice being given a cap.
47:01This is the epidmus,
47:03right? Then inside this testice, you
47:07have some sort of uh segments like this.
47:11Sorry.
47:18My test went away.
47:29It's not good.
47:33This is your testice, right? There's a
47:36cap
47:39given to the testice which is the pione
47:44inside the testice. You can divide the
47:45testice into several segments that are
47:49called as
47:51testicular lobules. Testes can be
47:54divided into testicular lobules. Inside
47:57these lobules you have mayhem a very
48:00tightly
48:04packed very long
48:08tube very tightly packed very long
48:13tube that is called what?
48:16Seminiferous tib all right seminiferous
48:19tube. So this is what it's going to look
48:22like. So semiferous tub
48:26it's a tube like this seminifpherous
48:28tub.
48:31If we look at the seminifpherous tubule
48:33like this
48:35this is what it's going to look like.
48:39Okay, this is what it's going to look
48:40like. So this is the wall of the
48:42semifpherous tubule. This is the wall of
48:45the semifpherous tibule.
48:47And if you take sperm,
48:50sperms are produced at the center.
48:55Sperms are found at the center. But
48:58sperms start their life in the corners.
49:02So this is the grandfather of a sperm.
49:04Then this is the father of a sperm. And
49:06homogill you get the sperms at the end.
49:10So the sperms begin their life as these
49:14cells.
49:15Later they become this nicely tadpoles.
49:19They become the sperm
49:22gradually.
49:23Okay. They start their life at the
49:25corner of the semiferous tibule and they
49:29undergo some changes
49:32to become the sperm.
49:34Okay. So that there's a diagram in your
49:37textbook as well.
49:42Great.
49:48sperms are formed. Right? We are on uh
49:51page
49:53page number 49 in the textbook. Okay.
49:57Science textbook. We are on page number
49:5949.
50:05Okay. I'll tell you what the app is.
50:07Okay.
50:09If you come to medicine, if you come to
50:11medicine, right?
50:16Right. It helped me in my first year.
50:19First year anatomy you need this
50:24uh in our sort of in our seniors time
50:27they used
50:29uh books. Now we have software. Okay. To
50:32do anything we have software.
50:48Okay. Sperms are formed from what? Sperm
50:53mother cells, right?
50:56Sperm mother cells.
51:02The sperm mother cells. These these are
51:06the mothers.
51:12So can anyone tell me
51:14these mothers
51:16are undergoing a cell division? A type
51:19of cell division when they are producing
51:21sperm. What is the cell division these
51:24mother cells are undergoing?
51:26If you want to produce a sperm
51:29meiosis meiosis
51:33meiosis elevation, you produce a sperm.
51:38Sperm of the cells are in the semiferous
51:39tubules. Sperms are temporarily stored
51:41in where within the training camp. The
51:45training camp for the sperm and from one
51:48end of the training cam sperms are sent.
51:53Training the sperms are sent out.
51:58Okay.
52:00Sperms are temporarily stored by
52:03rightd
52:07Dis so
52:10after the seminar is over or if you can
52:12do it even right now you can fill in the
52:16blanks in the tooth during the culation.
52:19What is culation?
52:22The sexual intercourse.
52:26Okay. During population sperm pass
52:28through what?
52:30This tube may black color.
52:33That is the sperm delivery tube.
52:37V difference.
52:40During population sperm pass through the
52:42vindas
52:45sorry V difference
52:47and collected to the urethra. At the
52:50same time the secretions of
52:54little
52:57right
52:59prostate gland and pus gland
53:13prostate and
53:16at the same time secretion of
53:24Seinal vesicle.
53:27Seminal vesicles. Seminal vesicle.
53:31Prostate
53:34and cooper.
53:38All three glands
53:41produce secretions.
53:43The secretion mixed with sperm is called
53:45what? Nice superapag. Right.
53:49Semen semen there are how many sperms in
53:531 milll you don't need the exact count
53:55right you say there are millions in your
53:59syllabus DNA
54:02all right in a healthy male there can be
54:04about four to five million
54:09then
54:12after couple after married couple have
54:14been trying to have a baby for more than
54:17one year Sorry 2 years
54:20for more than 2 years
54:23with proper right with proper technique
54:26and with the proper timing of the female
54:29reproductive system. If a couple has
54:32been trying to have a baby for two years
54:34and not successful that is
54:38subfile
54:40in that couple we don't know male the
54:42female
54:45skill issue right there is no skill
54:48issue everything else right now there is
54:50something wrong with the machinery right
54:54then you come to a doctor probably a
54:57gynecologist right female doctor
55:00gynecologist
55:01Because why? We assume it's always the
55:03female. We always assume it's the
55:05female.
55:07But almost 40% to 50% of the time it's
55:11the males. Okay.
55:15Okay. And what the first thing we do is
55:18the first thing a gynecologist is going
55:21to do is is to going to take a sperm
55:23sample semen sample from the man
55:25husband.
55:27Then we are going to analyze that semen.
55:30First thing that we are going to see is
55:32the sperm count. How many sperms are
55:35there in a milliliter?
55:37Okay. Then what? So if the sperm count
55:41is low, there is one reason to be not
55:44have children. Then another reason is
55:46what? So there's a sperm. This is a very
55:50let's say any kind
55:53sci-fi sperm connect, right? It's a very
55:55sci-fi sperm, right? Sperms. Then we
55:58look under the microscope at the semen
56:00sample to see if it's close to whatever
56:04this is. This is the proper shape. There
56:07can be sperms having a cute flag, right?
56:14Some sperms have two heads.
56:19Some sperms have a flag that is coil.
56:24I'm not joking. Okay. There can be
56:27different morphology right of sperm. So
56:32if sperms are abnormal then ethanima
56:35tagala you can find out if if it's the
56:37man's fault. If not then you are going
56:40to do a scan of the female ultrasound
56:43then other tests are done to see what's
56:45the issue with the couple. Right. Okay.
56:49Right.
56:53Why are testies located outside the
56:55body?
56:56Why are testies located outside the
56:58body?
57:03Testies are found outside the body man's
57:06the body of the male, right?
57:09>> Why is that?
57:13>> The sperm production.
57:18The sperm production
57:20is a very sensitive process the meiosis
57:23process. But more than that in the epid
57:26in the epidmis when the sperm is
57:29becoming mature
57:31it requires very specific conditions to
57:36be the proper sperm to be the proper
57:38sperm right to be the proper sperm right
57:42if those conditions are not properly
57:44there the sperm will be abnormal or even
57:47dead
57:48right so that's why sperms should be
57:52produced outside the body. So your body
57:55temperature is what can what is your
57:57body temperature if you don't have a
57:59fever? 37 to 38.
58:04This is too much.
58:08Sperms should close should be close to
58:10the room temperature otherwise
58:14they can be abnormal. So very sensitive
58:16to temperature. So the temperature of
58:18the test should be lower than the body
58:20for the production of healthy sperms.
58:23For the production of healthy these can
58:25be question structure is a paper they
58:27can ask you why
58:30our test is located outside the body. So
58:33the testes are in a skin sack
58:38called the scrotum in a skin sack called
58:40the scrotum.
58:45Okay.
58:49Right. If there's no other question. Ah
58:52yes.
58:58You don't need this many labels, right?
59:00Quickly label the sperm. What are the
59:02parts of the sperm? You have this C
59:06head.
59:10Uh B. Uh there's a neck. So, a neck
59:16neck of the sperm. Body of the sperm.
59:22Then there's the very long tail.
59:32Right. Quickly label it. Moving on.
59:36Moving on to the female reproductive
59:38system. Any questions? Do you have Do
59:40you have any questions? Right. Keep in
59:42mind the male reproductive system
59:47nothing much to do. Okay.
59:51What is scrotum? There's a question.
59:53Scrotum is composed of skin fold that is
59:58like a let's say a bag a bag for the
1:00:03testes. I'll show it when I'm with the
1:00:06software again. Right.
1:00:10Okay. female reproductive system.
1:00:13So I have to explain uh these
1:00:16structures in detail because uh
1:00:20I think I yesterday I showed you this
1:00:22right anyone hands up anyone who didn't
1:00:24watch the recording in the group
1:00:33okay right I know right
1:00:37it's fine Okay.
1:00:56Let's take a tour of the female
1:00:58reproductive system again. Let's take a
1:01:00tour of the female reproductive system
1:01:02again.
1:01:20I'll show you the scrotum first then.
1:01:22Right. So if you take a look at this uh
1:01:26this is the scrotum.
1:01:28What is the scrotum? What is the
1:01:30scrotum?
1:01:32This is the male male sort of body with
1:01:35uh with the skin. So this is the
1:01:38scrotum. Uh I think I didn't mention
1:01:42right naturally we have a covering over
1:01:46the tip of the penis. Tip of the penis
1:01:50right that is called the foreskin
1:01:53for skin.
1:01:55There's a covering, right? Sometimes in
1:01:58different cultures that foreskin is
1:02:00surgically removed, right? Surgically
1:02:03removed to
1:02:04expose this outer part
1:02:07that is called the glands. Glands which
1:02:11very sensitive the glands penis very
1:02:15sensitive.
1:02:16Okay.
1:02:20Clear. You can see the there are two
1:02:22scrotums I mean scrotal sacks right
1:02:26there's only one scrotum but it's
1:02:27divided into two for the two testic the
1:02:29kakiron
1:02:31clear
1:02:33right it come to the female
1:02:42so female reproductive system if we go
1:02:45like this right the female reproductive
1:02:48system Memi
1:02:52there are very few or you can say there
1:02:55are no external organs right there are
1:02:57no external structures okay female
1:03:00reproductive system there are almost no
1:03:02external structures everything is inside
1:03:04the female reproductive system
1:03:08is specialized to do two things
1:03:13to produce the egg and also most
1:03:16importantly if that egg is fertilized to
1:03:20nourish a future offspring, a baby
1:03:25adopted.
1:03:27Okay, male opening urinate.
1:03:31I hope you know these things, right? If
1:03:34you zoom in to the openings of the
1:03:37female reproductive system,
1:03:41this is the urethra. Okay, this is the
1:03:44urethra. This is where the urine comes
1:03:46out. Okay,
1:03:49this is the vagina. This is the
1:03:50reproductive opening. This is the
1:03:52reproductive opening. This is the
1:03:53urethral lo. So there are two openings
1:03:55in the female. But in the me male, it's
1:04:00the same opening. The urethra and the
1:04:02sperm comes out of the urethra. Okay. So
1:04:07let's see. I'll remove the skin and uh
1:04:14I'll remove the bones as well. Right?
1:04:19Then you can clearly see the internal
1:04:22structures of the female reproductive
1:04:24system. Okay.
1:04:27Uh some of these structures are not in
1:04:29your syllabus. So I'll remove Okay.
1:04:37Okay. Now we can uh I'll go from outside
1:04:40to inside. Right. So this is the opening
1:04:43of the female reproductive system to the
1:04:44outside. This is called the valva.
1:04:47Right? The valval opening. This is it.
1:04:50Right? This is the valval opening. Okay.
1:04:54This opening is called the valva. The
1:04:56valva gives rise to the right. That is
1:04:58the starting point of the muscular tube.
1:05:00That is called the vagina.
1:05:02Vagina. Right. This is this acts as the
1:05:05birth canal
1:05:08and sperms. Sperms are released into the
1:05:12vagina.
1:05:13Okay.
1:05:15If I remove the vagina, you can see the
1:05:18connecting point of the vagina to the
1:05:20uterus. Right? Connecting point of the
1:05:23vagina to the uterus.
1:05:26Right? This is called the cervix of a
1:05:28single gab. Gabill
1:05:32uterus. bail level, right? It's called
1:05:35the cervix. Then we come to the uterus,
1:05:38which is like a muscular bag. It's like
1:05:40a muscular bag for the baby to grow.
1:05:44What are the three parts of the uterus?
1:05:48One is cervix. This is called the body
1:05:51of the cerv sorry uterus. This is called
1:05:53the body of the uterus.
1:05:57You know then there's this place called
1:06:01the fondus where these two tubes these
1:06:04two tubes connect to the these two tubes
1:06:07connect to the uterus. What are the two
1:06:10tubes
1:06:12important? Right. The fallopian tubes,
1:06:16right? The fallopian tubes. Okay. So,
1:06:18the fallopian tubes are muscular tubes.
1:06:20And at the corner of them near your
1:06:24ovary, you have this finger-like
1:06:26projections called fimria. Fimria. Okay.
1:06:30We'll talk about the functions of fimria
1:06:32soon. Okay.
1:06:41Okay. All right.
1:06:44Then there's a ovary. This is the ovary
1:06:47which is the male sorry female gonad
1:06:50cross-section of the ovary. Right.
1:06:54I'll explain the structure of the ovary.
1:06:56So this is the female reproductive
1:06:57system in its uh basic nature. Right? uh
1:07:03if I take a cross-section like this
1:07:08very complicated right but uh it's
1:07:11actually very simple
1:07:13right this is the bladder this is the
1:07:16urethra this is the urine path
1:07:20this is the urethra this is the uterus
1:07:22is the vagina this is your let's say the
1:07:26last part of the large intestine this is
1:07:28the rectum is the anus
1:07:31ovaries is fallopian tubes.
1:07:35Okay, simple female reproductive system
1:07:37very simple
1:07:39but functioning very very complicated.
1:07:43Okay, functioning the male reproductive
1:07:46system function wise very simple but
1:07:47let's say structurally complicated but
1:07:50the female is very structurally simple
1:07:53but functionally more complicated. Okay,
1:07:57that's how it is. Females
1:08:00you can't you can never understand how
1:08:03they function. Right. Okay.
1:08:08Right. Come to your to
1:08:18right
1:08:21do the labeling
1:08:24things you need to know uh in this
1:08:26diagram. I think uh you need to uh be
1:08:28able to label this is
1:08:33phalopian tube
1:08:38fallopian tube. Uh these are ovary
1:08:46ovary. If you have any connection issues
1:08:48don't worry you can always watch the
1:08:50recording but I prefer you join the live
1:08:52class right and people who are in the
1:08:55live class you can share the zoom link
1:08:58bladder.
1:09:00This is the bladder urine bag. Okay.
1:09:02Bladder
1:09:04label with me if you are able to. Right.
1:09:06This is the vagina
1:09:09where the baby is coming out and also
1:09:11the sperm is released.
1:09:15The penis is put here. Right. Penis.
1:09:18Okay. Vagina. And uh
1:09:23this is what
1:09:25this opening of the vagina to the
1:09:28outside is called the valva.
1:09:37Oh yes, sorry. Uh this is the urine
1:09:40pathway from the bladder that is called
1:09:46urera
1:09:52quickly label. Okay.
1:10:09Can I pin my screen when other people
1:10:11are speaking? Uh, does my screen go
1:10:13away?
1:10:16Something happened like that?
1:10:22I am pinned.
1:10:33Am I not? I am pinned.
1:10:46Okay. How about now? I am the spotlight
1:10:48now. Okay. Right.
1:10:57better.
1:11:00Okay. Nice. Right.
1:11:05There's a question. If uh the male
1:11:07releases urine,
1:11:14if the male releases urine, where is it?
1:11:16Uh
1:11:21There was a question.
1:11:24What about E part? Uh E E part in male
1:11:29reproductive system. E
1:11:32where do you have E
1:11:36here?
1:11:38Ah this in the sperm there. Is that your
1:11:41question?
1:11:43These are actually mitochondria. Okay.
1:11:46These are actually mitochondria. Right.
1:11:50These are actually mitochondria because
1:11:51why the flag the sperm has to swim
1:11:57right? This mitochondria produces energy
1:12:01for the sperm to swim. These are like
1:12:04engines. Mitochondria engines. Okay.
1:12:07These are like engines.
1:12:17Yeah, sure. Uh, send a message, okay, to
1:12:21my class coordinator 070788
1:12:266624,
1:12:30right? Send a message to her as the
1:12:32class coordinator. She will add you and
1:12:35send you all the recordings. Right?
1:12:38Don't worry. Okay?
1:12:41send a WhatsApp message to this number.
1:12:44Okay, moving on. Right. Ovary. There are
1:12:48pair of ovaries close to the lateral
1:12:49walls of the pelvic area. Lateral means
1:12:51what? Depata to the closer to the sides
1:12:55uh in the abdominal cavity. In a
1:12:57cross-section of the ovary, there are
1:12:58two zones, right? Two zones you can see
1:13:01in this diagram also, right?
1:13:05This
1:13:07part
1:13:11Right? This outer part you can call it
1:13:14as the
1:13:16cortex, outer cortex.
1:13:20Okay? Then this inner part
1:13:24you can see it has the blood vessels and
1:13:27also some nerves.
1:13:29The inner part is called the medala
1:13:32right outer cortex and inner medala.
1:13:35Okay.
1:13:41So there are two zones known as uh
1:13:51cortex
1:13:59or are producing k or are producing what
1:14:03we call as follicles.
1:14:06A follicle is nice arrangement. A
1:14:08follicle is a nice arrangement. It's
1:14:10like this. You can see one follicle
1:14:12here. So a follicle is like a uh a
1:14:18superstar.
1:14:20So if you take a follicle, there's a
1:14:22main role in the center that is going to
1:14:24be a future egg.
1:14:27That's a future egg. And surrounding its
1:14:29future egg, you have so many supporting
1:14:32cells.
1:14:34a future egg and surrounded by
1:14:36supporting cells. So this is a fer
1:14:41right if you take like
1:14:43superstar singer
1:14:46following that superstar when she goes
1:14:48to concerts there's like a supporting
1:14:50staff right so it's like this this
1:14:53follicle has a
1:14:55cell that will become an egg in the
1:14:57future so there are so many supportive
1:14:59cells that are there are to protect
1:15:01nourish and do other things right so we
1:15:06say ova or Eggs are producing follicles
1:15:08right simple. So the cortex contains
1:15:11these follicles and
1:15:14I write. So you can see there are
1:15:18several stages of follicles. You can see
1:15:20several stages of follicles. You can see
1:15:23this is you can take it at the first
1:15:25stage and also almost second stage third
1:15:29and this important stage right five and
1:15:34right. Do you think all these things are
1:15:37happening at the same time?
1:15:41They are happening at the same time. But
1:15:43do you think it's like going in a cycle
1:15:45like this?
1:15:47What do you think?
1:15:50Do you think these follicles are going?
1:15:56No. Right. If you take
1:16:00imagine this is the first step of this
1:16:03process. This is the place where it
1:16:06becomes this big then it will release
1:16:08the egg and later it will become this
1:16:10and this and this okum right here in the
1:16:14same place. Okay, it happens in the same
1:16:17place of the ovary but we are drawing it
1:16:19in like a cycle like this because we
1:16:21need to show how they progress from one
1:16:25stage to the other right the follicles
1:16:29are not going around in the ovary. Okay,
1:16:31I I'm telling you this because when you
1:16:32come to A levels, we have to learn about
1:16:35this in much more detail. Okay, so this
1:16:39is the ovary tag label this,
1:16:43right? So
1:16:47your follicles that contain the future
1:16:50egg that contain the future egg starts
1:16:54as a primary follic superstar imagine
1:16:58it's a dream whatever
1:17:02they this egg has just entered the
1:17:05competition so it's only a primary f
1:17:09then it goes through some stages
1:17:12SMS
1:17:13The singer goes through some stages then
1:17:16he'll become a graphian follicle.
1:17:20Graphian follicle
1:17:24then we can call this as the mature
1:17:27follicle but you don't need it. Right?
1:17:29This is the mature right? Mature
1:17:32follicle.
1:17:34When it becomes a mature follicle the
1:17:37wall of the ovary. So this is the wall
1:17:39of the ovary. This is the wall of the
1:17:41ovary. It will break the wall of the
1:17:45ovary will break and the egg will be
1:17:48released. The egg will be released to
1:17:50the outside.
1:17:58It is called what we give this special
1:18:02name. What do you call release of an
1:18:05oation
1:18:07right? Right.
1:18:12not asleep. Okay,
1:18:19ovulation. Then after ovulation, so the
1:18:24superstar has gone. What has happened?
1:18:26Then what happened? These supportive
1:18:29cells I told you it has some supportive
1:18:30cells. They were training the superstar.
1:18:33They were giving him food and
1:18:37they took care of the superstar. or the
1:18:39superstar became superstar and left
1:18:42ovulation. What is going to happen? The
1:18:45remaining supporting cells are going to
1:18:47become a structure. It's a glandular
1:18:50structure. Okay.
1:18:54What do you call what do you mean by a
1:18:55gland?
1:18:58A gland can do gland can secrete. A
1:19:02gland secretes.
1:19:09If you take this gland, they secrete
1:19:11hormones.
1:19:15Tell me the name. What is this? What is
1:19:17this gland?
1:19:19What is the name?
1:19:22Corpus
1:19:27lutium. Corus lutium.
1:19:31Corpus lutium vat. He's going to remain
1:19:33for a few days. But these supportive
1:19:36cells are going to get tired and finally
1:19:39it's going to become a scar sky cacton
1:19:42that is called
1:19:46corpus skin corpus
1:19:50albbeans
1:19:54copus albbeans right if I tell again
1:19:58what are the stages you have primary
1:19:59follicle graphian follicle mature
1:20:01follicle ovulation happens then you have
1:20:03copus lutium copus albical
1:20:07Okay,
1:20:13this is the structure of the ovary.
1:20:16But let me know if I'm going too fast.
1:20:19Let me know if I'm going too fast.
1:20:28Which part do you want me to explain
1:20:30again?
1:20:34Hm.
1:21:32Yes. Uh I do physical classes. Okay.
1:21:34Class details I'll tell you later. Okay.
1:21:37I do physical classes, right?
1:21:51Right.
1:22:07Moving on.
1:22:29So ovaria we are still in the ovary
1:22:31production of oa uh starts at the birth
1:22:34of a female right I'm not going to uh
1:22:41contradict this so
1:22:45okay because I'm I'm I'm being very
1:22:47careful not to teach you uh anything
1:22:50that is I mean even if it's incorrect
1:22:53I'm not going to teach you the correct
1:22:55thing right now it's not the time to
1:22:57teach you even the correct thing because
1:23:00then confused confused exam so yes
1:23:03production of starts at the birth no
1:23:07okay anyway tube that comes out of the
1:23:11ovary enters into the long
1:23:14it's muscular
1:23:16muscular. Why is it muscular? Because
1:23:19the egg has to be transported through
1:23:22the fallopian tube by the contraction of
1:23:25the fallopian tube. By the contraction
1:23:27of the fallopian tube
1:23:40now in the end of this tube which is
1:23:42close to the ovary is a funnel like is
1:23:44funnel like. So what do you mean by a
1:23:46funnel? Maybe it's expanded like this
1:23:50but also it's expanded and also it has
1:23:52fingerlike projections called fimria.
1:23:56Fimria ch. So these finger-like
1:24:00projections are called fimria.
1:24:10These are important transferring the
1:24:12right. So memi so this in ovulation
1:24:17will be released here the egg will be
1:24:20released here
1:24:22what it's going to do is the fallopian
1:24:25tube it's going to use its fimria and
1:24:28also muscular contractions to sort of
1:24:32suck this into the fallopian tube
1:24:37uterus is a hollow structure right it's
1:24:40empty inside there are three zones.
1:24:44Okay, three zones. There's a fundus,
1:24:47body and cervix.
1:24:51The two fallopian tubes are connected to
1:24:53the zone called the fundus. The other
1:24:55end of the uterus is the cervix. Right?
1:24:57I showed you with the uh software vagina
1:25:01or the end of cervical canal. Vagina
1:25:04starts at the cervix and opens to the
1:25:06outside at the vulva. Valva is the
1:25:08opening of the female reproductive
1:25:10system. Right? So let's label this
1:25:12diagram taggala.
1:25:15Let's quickly label this diagram
1:25:19ovary.
1:25:21So when you are thinking about when you
1:25:22are labeling the ovary, think what are
1:25:24the two regions of the ovary? What are
1:25:26the two layers of the ovary? Make a
1:25:28label. What are these fimria? What is
1:25:31the function of fimria? To collect the
1:25:36what is this
1:25:38fallopian tube, right? fallopian tube.
1:25:45What do you call this part of the uterus
1:25:47where the fallopian tube connects? It's
1:25:48the fundus.
1:25:51This is sort of the middle part is the
1:25:54body.
1:25:56Body of what? Urus. This is the gap or
1:26:02cervix which is the neck of the uterus
1:26:04where the cervix connects to the
1:26:08vagina. So this is the vagina or the
1:26:11endoservical canal.
1:26:15Vagina or the endoservical canal. Right.
1:26:20Any questions
1:26:28to the tricky part? Uh functions of the
1:26:32female reproductive system. Did we talk?
1:26:34Uh yeah. No we had earlier right?
1:26:37functions of the female reproductive
1:26:39system. Oh no, I think it's uh yeah,
1:26:41after the uh after menstrual cycle.
1:26:44Okay.
1:26:47Yeah, I think I added it after menstrual
1:26:49cycle.
1:26:52Yeah.
1:26:57Okay. Right
1:26:59to talk about uh the menstrual cycle.
1:27:05May
1:27:07how do you understand the menstrual
1:27:09cycle?
1:27:11As the name says, I want you to refer
1:27:14this diagram, right? As the name says,
1:27:19menstrual cycle
1:27:24is a cycle.
1:27:26It happens again and again and again.
1:27:28The menstrual cycle happens again and
1:27:30again
1:27:32while the female is alive, right? for
1:27:34the entire lifespan of the female. So
1:27:37female
1:27:40no menstrual cycle takes place from
1:27:44puberty not I mean puberty
1:27:47first bleeding or the men
1:27:50puberty to there's something called
1:27:52menopause
1:27:55right
1:27:58at around age 45 to 50 the production of
1:28:02eggs by a female stops so the menstruals
1:28:06cycle takes place within this time
1:28:08period. So if you let's say uh the
1:28:12female uh started the period at age 10
1:28:18and got the menopause at 50. So for 40
1:28:22years
1:28:24there was a cycle happening on average.
1:28:28On average on average that depends from
1:28:31female to female average 28 days. Every
1:28:3528 true this can change. There are
1:28:38females the cycle happens every two
1:28:40weeks. There are females cycle happens
1:28:43every six weeks. Right? So this is the
1:28:47average
1:28:50roughly around every four weeks you have
1:28:52a full cycle.
1:28:56There are two places you can say
1:29:00the cycle takes place in relation to two
1:29:05locations.
1:29:06What are the two locations? Those two
1:29:09locations that's how we divide the cycle
1:29:13into two parts. Right. There are things
1:29:17that happen in uh
1:29:19the ovary. There are things that
1:29:22happening in the that are happening in
1:29:24the yes uterus.
1:29:28So it takes approximately 28 days.
1:29:34Okay. So I want you to understand first
1:29:38thing first thing that I want you to
1:29:40understand. So there are two places.
1:29:42There's the ovary. There's the uterus
1:29:45involved in the menstrual cycle. I'm
1:29:47going to take time I'm going to take
1:29:49time to explain the menstrual cycle.
1:29:51Right?
1:29:53So the first thing I want you to know is
1:29:56the ovary is the leader. Ovary tami.
1:30:00Okay. Ovary is the leader. Uterus is a
1:30:03servant. Or you can say uterus listens
1:30:06to the ovary. Yeah. Uterus
1:30:09listens to the ovary. uterus does what
1:30:12the ovary tells it to do.
1:30:16Okay, that's the first thing you need to
1:30:18know.
1:30:21So ovary, let's just focus on the ovary
1:30:24first. What's going to happen in the
1:30:26ovary is shown in these diagrams.
1:30:30This is the ovarian cycle things that
1:30:32are happening in the ovary.
1:30:35Right? So you can see I told you this is
1:30:38the growing follicle. There's a
1:30:40superstar in here. This is the superstar
1:30:42that is going to become the egg.
1:30:46All right. So, this is the part where
1:30:49the superstar is growing. Superstar is
1:30:51released. Now, this is the supporting
1:30:55cells that are undergoing some changes.
1:30:58Okay. So, that is called the ovarian
1:31:01side.
1:31:03Then what's going to happen in the
1:31:04uterus? in a uterine
1:31:07this
1:31:10the uterus the uterus as I told you is
1:31:13listening to the ovary ovary whatever
1:31:15the ovary tells the uterus to do it's
1:31:18going to listen and
1:31:21uh follow
1:31:23right what I want you to have an
1:31:25understanding is if there is a
1:31:28fertilization what do you mean by a
1:31:30fertilization
1:31:36That means
1:31:40this egg that was released this egg that
1:31:43was released needs a sperm. This egg
1:31:47that was released meets a sperm
1:31:54and results in
1:31:57a zygote. results in a zygote
1:32:01that is called fertilization.
1:32:04So the your the uterus is very hopeful
1:32:09the uterus is very hopeful. He thinks
1:32:13every time the ovary releases an egg the
1:32:17female is going to get pregnant.
1:32:20Okay.
1:32:21He thinks
1:32:23the uterus thinks every time the ovary
1:32:28releases an egg, the female is going to
1:32:31get pregnant,
1:32:34right? Very hopeful.
1:32:38That's why the uterus prepares. Urus is
1:32:43like a house. Okay. So uterus he thinks
1:32:49there's going to be a baby. So the
1:32:52uterus prepares to welcome that baby
1:32:55every time you have an egg. So mine
1:32:59always follow the lines. So this dotted
1:33:01line this dotted line
1:33:06is the point in where is the point in
1:33:08the cycle where
1:33:11uh
1:33:13the egg is released. So this line is the
1:33:16point in the cycle where
1:33:19the egg is released. Okay. When you have
1:33:22ovulation.
1:33:24So he thinks there's going to be a
1:33:27fertilization here.
1:33:29He prepares the house. The uterus
1:33:32prepares to welcome a baby by growing
1:33:36thicker. Thick. The uterus becomes
1:33:40thick. It grows new blood vessels. It
1:33:43grows new glands. Right? It prepares to
1:33:46be pregnant. Uterus prepares to be
1:33:50pregnant.
1:33:52But the problem is
1:33:54almost
1:33:56every cycle there is no pregnancy.
1:33:59If you average female
1:34:02average female usually have only one
1:34:04child or two children. So in this
1:34:0840 sorry 50 I mean this 50 years
1:34:13she might have only two children.
1:34:18So almost all cycles end with
1:34:24sad story. What is the sad story?
1:34:27There is no baby. So what the uterus
1:34:31prepared for has to be broken down.
1:34:35We say
1:34:36the new bed sheets everything has to be
1:34:39removed because there is no baby to
1:34:41welcome right that is what we see as the
1:34:45menes or the bleeding
1:34:55so
1:34:57that's what is happening physically
1:35:01right
1:35:03ovary is releasing an egg and the uterus
1:35:06is preparing to receive a baby but there
1:35:09is no baby so the uterus is breaking
1:35:12down the what he prepared that is what's
1:35:15happened okay
1:35:29so then we have to come to this sort of
1:35:35How hormonal levels, different hormones
1:35:38control these two things, the ovary and
1:35:41the uterus. How are they regulated by
1:35:43different homes? Right? Let's see.
1:35:50Right? Come to this filling the blanks
1:35:52place. Right? So on this side we have
1:35:56things happening in the ovary.
1:36:01Right? So first what did we have? We
1:36:03have the phase where the follicle is
1:36:06developing. We are training the egg. we
1:36:09are training the egg or the superstar to
1:36:11be released. that is called where you
1:36:13have follicles right follicle is getting
1:36:16mature so it's called the follicular
1:36:18phase
1:36:20okay
1:36:24once the egg is raised I told you
1:36:27there's a gland like thing that is
1:36:29forming that is called the corpus lutium
1:36:32so when you have a corpus lutium that
1:36:34time period is called lutary phase
1:36:44glutial phase.
1:36:46These are the two ovarian stages. So
1:36:48let's read this is the initial phase
1:36:51under the influence of the FSH hormone
1:36:54secreted by the pituitary gland.
1:36:56Pituitary gland is located in your
1:36:58brain. Okay? Right? Pitary gland is
1:37:00located in your brain.
1:37:02A primary follicle in the ovary develops
1:37:05to form a graphian follicle. I you know
1:37:07this right? This is step number one.
1:37:09Then it becomes a graphian follicle.
1:37:11Then it becomes a mature follicle.
1:37:14Then it gets ready to release an O. It
1:37:16takes about 14 days.
1:37:19During this phase ovary secretes
1:37:22estrogen hormone
1:37:24diagram. Let's see the diagram.
1:37:28What is the hormone that they saying?
1:37:30Green color.
1:37:33Green color. FSH.
1:37:36Right. So follow this. Can you see this
1:37:39green color? FSH
1:37:41is promoting me. The FSH level is sort
1:37:45of increasing. So that is stimulating
1:37:47these follicles to grow grow grow right
1:37:51because the follicle is growing growing
1:37:53growing there is secretion of estrogen
1:37:59or you can say estradiol.
1:38:02Estrogen hormone levels are increasing,
1:38:04increasing, increasing, increasing.
1:38:07Okay. So, can you see? So, this is what
1:38:12what is this face?
1:38:14If you take the ovary, this is the
1:38:19follicular phase
1:38:23near the this is the follicular phase.
1:38:26So, at the same time, what is happening
1:38:28in the uterus? So you can say it says
1:38:32the follicular phase.
1:38:34What is happening at the uterus is
1:38:37called
1:38:40proliferative phase.
1:38:46When the ovary is doing the follicular
1:38:48phase
1:38:50uterus is going through what we call as
1:38:52the plur proliferative phase. So let's
1:38:55read about the pliferative.
1:38:56proliferative or proliferative.
1:38:59Jump to the uterus. Uterus is going
1:39:02through
1:39:04proliferative.
1:39:17Sorry.
1:39:27Or you can say in your in your
1:39:31textbook it says puriferation
1:39:33puriferation phase purif proliferation.
1:39:37So this is the initial phase.
1:39:41Just ignore this first part. Right?
1:39:45Oh wait wait wait hold on hold on.
1:39:50Right.
1:39:52small small error right
1:39:56because this is how your textbook starts
1:39:59that's how I made this tube but I want
1:40:01you to understand that this follicular
1:40:06phase of the ovary is actually matching
1:40:09nicely with the what
1:40:13second base that is the proliferation
1:40:20acre map
1:40:22this thing also is happening right the
1:40:24first and the second things are actually
1:40:26happening at the same time as the
1:40:28follicular phase right at the same time
1:40:31as the follicular why do I say that
1:40:33diagram when you have a doubt just go
1:40:35and look at the diagram can you see
1:40:39even though we I call this the
1:40:40pliferative phase this part they say
1:40:44menes
1:40:45they say menes that means what
1:40:49there is bleeding there is some breaking
1:40:52down of the uterus happening during the
1:40:57follicular phase. So actually follicular
1:41:00phase of the ovary is combination of
1:41:03menstrual phase
1:41:06where you have the bleeding
1:41:08plus proliferative we can during the
1:41:11follicular phase you have both menstrual
1:41:14and proliferative happening in the
1:41:15uterus.
1:41:18Okay. So menstrual phase right? So let's
1:41:25talk about the menstrual phase that is
1:41:27this one later. Let's talk about it a
1:41:29bit later. Right? So what is happening
1:41:33in the proliferative phase? The wall
1:41:36start to rebuild because by the uterus
1:41:40is very excited. I'm going to get a
1:41:43baby. Okay. So he starts to rebuild
1:41:48under what hormone estrogen. Can you
1:41:51see? Because the growing the ovary was
1:41:54secretting estrogen that estrogen is
1:41:57here.
1:41:59It's helping the uterus to build a new
1:42:03layer.
1:42:04New cell layer and blood capillaries
1:42:06grow. It takes about 10 days.
1:42:10Okay.
1:42:12Can you see? Then proliferative phase 10
1:42:16days. Usually if you ask any female
1:42:21way right it's mentioned here right it
1:42:24is about 4 days
1:42:27proliferative phase is about 10 days
1:42:30menstrual phase is so I'll label this
1:42:34this is menstrual
1:42:39menstrual phase is about also it's about
1:42:414 days now can you see follicular phase
1:42:45was 14
1:42:47follicular phase was 14 face.
1:42:52So
1:42:55you can see follicular phase you have
1:42:58both menstruation and sorry yes
1:43:00policular you have both menstrual and
1:43:03proliferation happening
1:43:06right then let's come to back to the
1:43:09ovary and see what is happening in the
1:43:11lutal phase right so now the egg goes
1:43:14released ovulation happened what do you
1:43:17have left I mean it bursts and the is
1:43:20released
1:43:22and into the fallopian tube under the
1:43:24influence of there's a new hormone
1:43:27called this
1:43:29there's a new hormone
1:43:32called the lutal hormone
1:43:35we call it LH lutal hormone
1:43:39lutal hormone is secreted by who
1:43:43same as FSH pit
1:43:47pitary
1:43:49Okay. Same as uh FSH pitutary.
1:43:54If fertilization does not occur, the O
1:43:57is passing forward through the fallopian
1:43:58tube, right? Then what? There is no
1:44:03baby, right? What is going to happen?
1:44:07The supportive cells of the follicle
1:44:09that were left behind changes to become
1:44:14corpus lutium.
1:44:19not sleeping right. Corpus lutium. Copus
1:44:22lutium is this. This is glandular. This
1:44:26is gland. Corpus lutium is like a gland
1:44:28but it will become copus albbeans. Copus
1:44:31albbeans is like a scar.
1:44:35It's like a old wound. Okay. So it will
1:44:38become a a scar albbeans and um fades
1:44:42off. Uh lutal face also takes about 14
1:44:47days.
1:44:48Dhatra dhatra you have 28 total days
1:44:51during this phase the ovary secretes
1:44:53progesterone.
1:44:55Okay come to the diagram and see what is
1:44:58happening in the lutal phase. We start
1:45:01our lutal phase after ovulation. After
1:45:05the egg has
1:45:11we start our lutal phase after
1:45:14ovulation. after ovulation. Very very
1:45:16important. We start our lutal phase
1:45:19after ovulation.
1:45:22Right?
1:45:24So
1:45:26they say why is ovulation happening?
1:45:29Because of luteinizing hormone. Can you
1:45:31see the luteinizing hormone?
1:45:35The luteinizing hormone was at a lower
1:45:37level.
1:45:40Suddenly it increased rapidly then it
1:45:43went goes down again. This rapid rise of
1:45:46the luteinizing hormone is going to do a
1:45:49ovulation.
1:45:52That is going to do ovulation.
1:45:55So if they ask you what is the hormone
1:45:57responsible for
1:45:59ovulation who is it luteinizing hormone.
1:46:05So they also say during this time who do
1:46:08you have? You have copus lutium. Copus
1:46:11lutium is going to do what?
1:46:14Copus lutium is satala say creating who?
1:46:19Proester. Can you see the purple color
1:46:22progesterone?
1:46:24Very high.
1:46:27Right.
1:46:31Okay.
1:46:33So let's come to this now. What is going
1:46:36to happen in the
1:46:39can? What is going to happen in the
1:46:41uterus? Urus what we call as the
1:46:43secretary phase. Secretary
1:46:49secretary means you are secretreting
1:46:51something. You are releasing something
1:46:54secret right? That's what's going to
1:46:56happen in the secretary.
1:47:00Secretary phase let's read
1:47:03this is the final phase.
1:47:09uterine wall thickness, blood supply
1:47:11increase, glands are activated. Ah,
1:47:15that's why we call this secretary phase.
1:47:17Because why? You have glands that are
1:47:20secretreting
1:47:22fluid. There is a fluid.
1:47:24Why are we secreting this fluid? Because
1:47:27if there is a pregnancy, that first baby
1:47:32should have some nutrition. that
1:47:34nutrition will be provided by these
1:47:36glands.
1:47:39That happens because of the hormone
1:47:40progesterone. I told you right
1:47:42progesterone peak
1:47:45we are in a very high level of
1:47:47progesterone. It takes about 14 days.
1:47:50Body temperature also increases
1:47:52slightly.
1:47:54Okay.
1:47:56This is this line.
1:47:59This line is a body temperature line.
1:48:01This red color line I hope you can see
1:48:04this red color line is body temperature
1:48:08is body temperature. So when a female is
1:48:12in the lutial phase or the secretary
1:48:14phase their body temperature is slightly
1:48:17high
1:48:20slightly high.
1:48:22Okay body temperature is slightly high.
1:48:28You females feel this right? When they
1:48:31are in the secretary phase they feel
1:48:34they have sort of like a
1:48:37duck body warm tak right their body
1:48:40temperature is high. Follow this line
1:48:42body temperature line.
1:48:49Okay.
1:48:52I'll explain again.
1:48:56Okay. We'll explain again. Any
1:48:58questions? Always
1:49:01always follow this diagram. This is your
1:49:04diagram.
1:49:08What are the questions that you have?
1:49:30Send your questions to the main chat
1:49:38blank completed to the group as well.
1:49:40Yeah, sure. I'll send
1:49:43can we have a break.
1:49:46Okay.
1:49:48Right. Sure. Uh there's a question. So
1:49:52after menopause a female cannot give
1:49:54birth to a child. No, of course. Because
1:49:56why? There is no eggs. No eggs coming
1:49:59out. Right. Okay. Uh take a small break.
1:50:0210 minutes. Okay. Then I'll uh
1:50:08explain this again. Okay. Take a small
1:50:11break.
1:50:1610 minutes. 10 minutes break. Okay.
1:50:26Join back in 10 minutes.
1:50:34Okay. Join back in 10 minutes.
1:51:24This is amazing.
1:51:48Good morning.
1:52:41Focus.
1:53:01All right.
1:53:33I'm very
1:55:09Thank you.
1:55:14Hallelujah.
1:59:58Okay. Uh
2:00:01shall we start again?
2:00:45shall we Perfect.
2:02:46Okay. So, can you hear me? All good.
2:02:50Right. Okay. Right.
2:02:53Let's start. We have a lot more to cover
2:02:54today.
2:03:05Okay. Right. If I explain menstrual
2:03:08cycle again. Right. If I explain the
2:03:10menstrual cycle again.
2:03:38So
2:03:41we have two organs that are involved in
2:03:44the menstrual cycle in the female. You
2:03:46have the ovary that is going to undergo
2:03:50the ovarian side. You have the uterus
2:03:53that is going to undergo the uterine
2:03:55side.
2:03:56Ovary is the loca. Ovary is in control.
2:04:00Whatever ovary is doing, it will be
2:04:02followed by the uterus. Ovary has two
2:04:05parts as the follicular phase and the
2:04:07lutal phase. Follicular phase is where
2:04:11the follicles start to grow up to until
2:04:15there is the ovulation. Egg is released
2:04:18from the ovary. Lutal phase is from
2:04:22ovulation forwards. All right. And
2:04:26follicular phase there are two parts of
2:04:28the uterine phase that is the menstrual
2:04:31phase and the proliferative phase.
2:04:33proliferation. Okay. Right. In the
2:04:36menstrual phase, what is happening is
2:04:38there is bleeding, right? From the
2:04:40previous cycle, the uterus that was
2:04:42built up will be broken down. It will be
2:04:47like a flow of blood from the vagina
2:04:51coming out. It will contain some of the
2:04:54these secretions, clotted blood and also
2:04:57some tissue. Right.
2:05:00Right. It it contains this uterine
2:05:03layer, right? The layer of the uterus.
2:05:05It's like a carpet, right? The carpet
2:05:07was laid down. What? Because of what?
2:05:12The carpet carpet was laid down because
2:05:16the uterus thought
2:05:19there is a baby
2:05:21on the way. The uterus thought there's a
2:05:23baby on the way. That's why
2:05:28it was prepared but baby didn't come. So
2:05:31that uterus lining is going to be broken
2:05:34down. Menstrual place and you have the
2:05:36proliferative. In the proliferative
2:05:38phase what is happening is because of
2:05:40this estrogen this uterus layer is
2:05:43getting bigger bigger bigger. At the
2:05:46same time there's another two hormones
2:05:48that are called FSH and LH that are
2:05:51secreted by who?
2:05:54Pituitary gland
2:05:57pituitary gland in the brain
2:05:59particularly FSH is going to control
2:06:02this follicular phase that is the
2:06:04growing of the follicle. As the name
2:06:06says natino follicle stimulating hormone
2:06:11it stimulates the growth of follicles.
2:06:14Very simple
2:06:16right? So then at the end of follicular
2:06:19phase there's going to be another
2:06:20hormone called luteinizing hormone that
2:06:23is going to cause ovulation. There's
2:06:26going to be a peak in the LH that is
2:06:28going to cause ovulation. That is the
2:06:30end of the follicular phase. Then you
2:06:33have the secretary phase where
2:06:36the uterine lining becomes even more
2:06:38thicker and thicker and thicker
2:06:41that is to welcome the new baby. So when
2:06:45that is happening
2:06:47you have in the ovary this glandular
2:06:50structure left behind after the o was
2:06:53released that is called corpus lutium.
2:06:55Corpus lutium secretes the progesterone
2:06:57hormone that is going to make the
2:07:00uterine lining thicker and thicker and
2:07:02thicker.
2:07:04But because there is no pregnancy this
2:07:06corpus lutium is going to die. It will
2:07:09become have a skyak that is called the
2:07:11corpus albus. Copus albbeans
2:07:16is not secretreting anything. It's not
2:07:18secretreting anything. It's just a scar.
2:07:22It's like a wound that was healed. So
2:07:24the whole hormones levels are going to
2:07:26come down. The progesterone estrad
2:07:29coming down. Therefore this uterine
2:07:32lining will not be maintained. It will
2:07:34break down.
2:07:36It will break down. So that's why you
2:07:39have bleeding.
2:07:41Very simple. This is the uterine side.
2:07:43Sorry. Uh this is the menstrual side.
2:07:46Any questions you have?
2:07:52Okay.
2:07:55Right.
2:08:00Now we can come to
2:08:02if if there was a sperm if there was a
2:08:06sperm coming right. If there if a sperm
2:08:09came from the vagina, right? If a sperm
2:08:12came, right? So this is like a part of
2:08:15the uterus.
2:08:17If there was a sperm
2:08:20outper, can you see here? You can see
2:08:22the sperms.
2:08:24If a sperm came, so the female had
2:08:28sexual intercourse and if a sperm came,
2:08:31there can be fertilization. If
2:08:33fertilization happens, what can you
2:08:35have? There can be a future baby, right?
2:08:39So the future baby starts with when you
2:08:42plug the baby, right? You have to plug
2:08:44the baby into the uterus lining for it
2:08:47to grow bigger and bigger,
2:08:51right? What is it?
2:08:55Copulation. Copulation can having sex.
2:08:57Okay. Copulation is the sexual
2:09:00intercourse. Seinal fluid will be
2:09:03released from the penis into the vagile.
2:09:05Right.
2:09:08sperm cells swimming right
2:09:13pass through the uterus towards the
2:09:14upper part of the fallopian tube right
2:09:17fertilization
2:09:19the fertilization happens in the upper
2:09:21part of the fallopian tube. So can you
2:09:24imagine the distance the sperms have to
2:09:26swim
2:09:29right?
2:09:31Sperms have to swim such a long
2:09:33distance.
2:09:35Let's go up and see the full anatomy.
2:09:40Can you imagine how long the sperm has
2:09:42to swim?
2:09:44Imagine the sperm came I mean the sperm
2:09:47should come from here from the vulva.
2:09:50Oh, mila. Right. Through the vagina,
2:09:53through the cervix, through the uterus,
2:09:55through the fallopian tube up to the
2:09:57sort of the end of the fallopian tube.
2:10:00Sperm has to frame. Right? It's like a
2:10:03marathon for the
2:10:06sperm.
2:10:07That's why sperm have to be very very
2:10:09healthy. They have to be very active,
2:10:12very motile. Family sperm, lazy sperm,
2:10:15theora
2:10:17that man is sort of sort of less able to
2:10:22produce children, right? Pass through
2:10:24the uterus towards the upper part of the
2:10:26fallopian tube. Then one of the sperm fu
2:10:29fuses with the passing through the
2:10:31uterus. Here the nucleic matter of the o
2:10:34right? So the o has a nucleus and the
2:10:38sperm fuses together. This is called
2:10:40fertilization.
2:10:41Fertilized Om is known as skin
2:10:46zygote.
2:10:53While it is rolling towards the uterus,
2:10:54it divides into the number of cells to
2:10:57increase the number of this is then it
2:10:58is known as morula
2:11:04which disintegrates the tissue of the
2:11:06uterine wall sinks and deposits into the
2:11:08wall. This is known as implantation.
2:11:14So your zygote is a single cell.
2:11:18Your zygote is a single cell. Can you
2:11:21see
2:11:22this is the egg
2:11:24or the oven.
2:11:33Okay. This is the egg. Now can you see?
2:11:35I think you can see in your tubes but
2:11:37not in this screen. And you have the
2:11:39sperms here. The sperms come into the
2:11:42egg. Then the sperm has its nucleus. So
2:11:46this is the zygote. This is the zygote.
2:11:49This is also zygote.
2:11:54Actually the zygote is the egg cell with
2:11:56the sperm inside. It's the egg cell with
2:11:59the sperm inside.
2:12:03Then it starts to divide. So you can see
2:12:07within so this is day one egg is
2:12:11released day two fertilization day 3 4 5
2:12:146 within 7 days this is the morula
2:12:18morula will arrive at the uterus
2:12:23right morula will arrive at the uterus
2:12:25through the fallopian tube then it will
2:12:30sort of deposit what we it's actually
2:12:32very invasive it's like
2:12:35Right? You are plugging the morula. We
2:12:39don't call it the morula. We actually
2:12:40call it the blastoyst. You don't know
2:12:42need that name. Right? It's actually you
2:12:45plug the morula or the this bowl of
2:12:47cells into the endometrium or the inner
2:12:51layer of the uterus.
2:12:55That is called what?
2:12:58Implantation.
2:12:59Implantation.
2:13:05implantation.
2:13:10Okay. So this is a diagram of an egg.
2:13:14This big thing is an O, right?
2:13:18Surrounded by what? Our surrounded by
2:13:21thousands of eggs
2:13:24plus thousands even. Yes. Thousands of
2:13:26eggs,
2:13:29right? Only one is a winner.
2:13:33So you know the semen has about so
2:13:38semen has about 5 ml 5 to 10 milll 1
2:13:42milll has about four to five million
2:13:47right so average about 25 million sperms
2:13:52are released
2:13:54right out of that only about a few
2:13:56thousand 5,000 10,000 sperms reach the
2:14:00egg Right? So out of those there is only
2:14:03one winner. There's only one is going to
2:14:07go into the egg and fertilize it.
2:14:10There's only one winner.
2:14:13Okay.
2:14:14So this is a surrounded by sperm. Then
2:14:18development of the fetus.
2:14:21So after implantation what's going to
2:14:23happen? Mitosis. Mitosis. Mitosis.
2:14:25Mitosis. Right? What is the cell
2:14:27division? It's always going to be
2:14:29mitosis.
2:14:32In about 6 weeks, protective membranes
2:14:35called can
2:14:37embryionic membranes.
2:14:42Okay? Embriionic membranes develop.
2:14:48Embionic membranes. There is four
2:14:50embanic membranes. You don't need this,
2:14:52right? I'll give you one name that is
2:14:56called
2:14:57amnon.
2:14:59There's a membrane called amnium
2:15:04amnotic fluid.
2:15:08There's a fluid in them. There's a sunk
2:15:10in this fluid.
2:15:13Have you heard of something called
2:15:15pregnant mothers saying pregnant mothers
2:15:19water breaking?
2:15:22Water break.
2:15:24Have you heard
2:15:26water bag broke? Water bag,
2:15:30right? Water bag breaking means one of
2:15:33these embanic membranes breaking that is
2:15:36the amnon breaking and this whole baby
2:15:39is in water. It's in the water called
2:15:44uh amniotic fluid. So that fluid is
2:15:48coming out when the baby is just about
2:15:50to be born.
2:15:51That's why we say
2:15:55it's one of these embanic membranes has
2:15:57broken and the fluid has come out.
2:16:01There's a question what will happen to
2:16:03the other sperms? They just they are
2:16:06just absorbed into the female system.
2:16:08They are just absorbed or digested into
2:16:10the female system.
2:16:13They don't matter. Right? Uh the place
2:16:17the embriionic membranes connect with
2:16:19the uterine wall is called kin.
2:16:24This is a very nice place that is called
2:16:26the placenta. Very nice structure called
2:16:30the placenta.
2:16:32Placenta
2:16:35is like a plug base. Right? Placenta is
2:16:39like a plug base. So
2:16:43here can you see
2:16:46this is the placenta.
2:16:50Okay. So he put another diagram.
2:16:54See this is a real image of a preserved
2:16:57baby. Okay. Right. Uh preserved baby
2:17:00from a uh I mean the baby did not
2:17:04survive. Right. Uh
2:17:09this is the placenta. Can you see this
2:17:11is the placent?
2:17:15And uh can you see I'll use a yellow
2:17:18color. This entire thing is the uterus.
2:17:22This is the uterus.
2:17:24Okay. So your placenta
2:17:28is like a plug base that is going to
2:17:33connect. What is a plug base? Right? So
2:17:37there is a wire code. Right? If you have
2:17:39a plug,
2:17:43if you have a plug name,
2:17:47right, and at the corner of it, you have
2:17:51this sort of plug, right? Imagine. Then
2:17:55you need what? In the wall, you need
2:17:59a plug base. This is the plug and the
2:18:01plug base. So here imagine you have uh
2:18:06maybe electrical appliance or TV
2:18:10right so this TV is like the baby
2:18:13there's a wire code that is called wire
2:18:16code is called what
2:18:18the wire code that is connecting the
2:18:20baby to the mother is called the
2:18:22umbilical code
2:18:25it has code in its name it's like a wire
2:18:28code this plug that is connecting the
2:18:32baby to The mother is the placenta.
2:18:37Placenta has actually two parts that is
2:18:39the plug and also plug base is also part
2:18:42of the placenta. Placenta has two parts.
2:18:46Right? The one part is belonging to the
2:18:49mother, one part is belonging to the
2:18:51baby. So this is the baby. Baby is not a
2:18:55TV but right this is the baby. This is
2:18:58how the baby is connected to the mother.
2:19:01Right?
2:19:09So
2:19:12that's what's going to happen.
2:19:15Material exchange from the mother to the
2:19:17fetus and fetus to the mother occurs
2:19:19through Yes.
2:19:22What is the plug plug code?
2:19:27Umbilical
2:19:33code
2:19:36mostly umbilical code is there to
2:19:41give nutrients and also oxygen to the
2:19:43baby because why the baby can can the
2:19:45baby breathe? Can the baby breathe?
2:19:50The baby is in a liquid. The baby's
2:19:53is in a liquid. baby malic the baby
2:19:56can't breathe so oxygen everything has
2:19:59to be given by the mother so that oxygen
2:20:02comes through the ambilical
2:20:06but the problem is some diseases right
2:20:11what are the diseases that you know that
2:20:12can come to the baby from the mother
2:20:14what is the most severe thing can be HIV
2:20:19some others right that can come from the
2:20:23mother to the baby through the umbilical
2:20:27cord and through the placenta. Okay.
2:20:31Some diseases
2:20:34very very important. I told you I mean
2:20:37this placenta is a connection between
2:20:42the baby and the mother. But mother's
2:20:45baby never mother's blood never comes
2:20:49into the baby. It is only material
2:20:52exchange. Only nutrients, oxygen and
2:20:55sometimes
2:20:57pathogens can come and go. But there is
2:20:59no mixing of blood. Blood exchange does
2:21:03not occur. It is modified like that.
2:21:07Okay. It is modified in a such a way
2:21:10that there is no blood
2:21:15exchange
2:21:18between the baby and the
2:21:22baby and the mother.
2:21:26Okay,
2:21:31there's a diagram in the in your
2:21:33textbook that is showing you the
2:21:35pleasant nicely. That's why I didn't put
2:21:37a diagram, right? Placenta and the
2:21:40umbilical code. I'll show you when I'm
2:21:42screen sharing again. So, you can label
2:21:45these diagrams. You can label these
2:21:46diagrams.
2:21:52Right?
2:21:53Label these diagrams. This is zygote.
2:21:55This is a zygote. You can see the two
2:21:58male and the female nucleus. This is uh
2:22:03uh this is also a zygote that is just
2:22:05about to start dividing to become a
2:22:08morula. This is 11 weeks. This is 12
2:22:12weeks. This is uh 18 weeks baby.
2:22:17Finally, this is 19 week baby. And
2:22:21finally, this is a 23 week baby.
2:22:26Okay. How long is the pregnancy?
2:22:30How long is the pregnancy?
2:22:37How long is the pregnancy?
2:22:40Can How many weeks is the pregnancy?
2:22:44Yes. 9 months.
2:22:49Yes. 36 to 38 39 weeks. Average 38
2:22:53weeks, right?
2:22:59So this is a 23 week baby. Uh right as
2:23:03homework what I want you to do is
2:23:06fill this chart with the different uh
2:23:11month. What happens in 3 months, 4
2:23:14months, 5 months,
2:23:176 7 8
2:23:20and 9 months. What are the significant
2:23:22things that are happening in these
2:23:24milestones? Right? For example, at the 3
2:23:27months, male sex organs are completely
2:23:30developed, right? Completely means,
2:23:32right? You can see, right? At 3 months
2:23:36means how many weeks? 12 weeks. You can
2:23:39see the genitalia, right? You can see
2:23:41the male and female genitalia. And when
2:23:44you do an ultrasound, right?
2:23:47You do the first ultrasound at 3 months,
2:23:50right? When the mother is pregnant, you
2:23:53do the first ultrasound scan as 3 months
2:23:56and uh that ultrasound scan will show
2:24:00you if you are having a boy or a girl.
2:24:02Okay. Uh then four months are the
2:24:05skeleton
2:24:08then 5 months uh fetal movements very
2:24:11very important and also heartbeat. the
2:24:15heart starts to beat
2:24:17usually
2:24:19at fifth month we say yeah around 20
2:24:23weeks yes 20 weeks 36 I mean 6 months
2:24:27nothing much important seven uh skin is
2:24:30wrinkled right uh 7 months means uh how
2:24:34many weeks
2:24:37about 28 weeks right skin is kind of
2:24:39wrinkled can you see
2:24:43right because why the baby is not having
2:24:45that much body fat. Body fat is a bit
2:24:47low. Therefore, the baby's skin is a bit
2:24:50wrinkled. Right? Afterwards, uh then can
2:24:53you see in 8 months fat deposition start
2:24:56to happen. 9 months what's going to
2:24:59happen?
2:25:02Test have come to the scrotum.
2:25:06You might ask where the test is uh
2:25:09before 9 months.
2:25:15Right? Where were the testice before?
2:25:18Actually,
2:25:20your testice were are inside your body
2:25:24before you are born. Right? The testice
2:25:26are inside your body. They are not in
2:25:28the scrotum.
2:25:31When you are in your mother's uterus,
2:25:33but uh when you are just about to be
2:25:36born, the testice
2:25:38comes into the scrotum and settles.
2:25:41In about every one boy out of three,
2:25:44every three, every one male boy out of
2:25:48three babies
2:25:49is not going to have the testice in the
2:25:52scrotum when they are
2:25:54uh born. It's not late blooming. We call
2:25:57it delayed descent. Okay, testies test
2:26:02haven't descended. But within the first
2:26:046 months of being a baby the testice are
2:26:07going to come out into the scrotum right
2:26:11it's an issue okay sometimes we have to
2:26:13do a surgery within one year if the
2:26:15testes are not in the scrotum problem
2:26:18sometimes we have to do a surgery okay
2:26:21right that is homework
2:26:24right
2:26:26to the endame
2:26:31final get a finished product what is it
2:26:33a full baby. All right. When the baby is
2:26:37close to be born,
2:26:40usually the baby is usually lying with
2:26:42the head in this direction.
2:26:46If the baby is going to be born
2:26:47normally, right on the
2:26:51normal behave in a baby, the baby is
2:26:55going to turn on the is going to do a
2:26:58nice roll over and the head is going to
2:27:01come to the
2:27:03lower end and then it's easy for the
2:27:06child birth because why the head is the
2:27:09biggest part. So if the head comes out
2:27:11first then it's very easy. So it's this
2:27:14is the sort of standard way. The neck is
2:27:16going to be sort of the flex like this
2:27:19and the baby will be pulled out.
2:27:22Right? So this is the baby coming out.
2:27:24And finally what's going to happen is
2:27:26this placenta
2:27:29this placenta should be separated from
2:27:32the uterus. uterus walling the placenta
2:27:35should be removed separated and with the
2:27:38so ambilical code is cut right when the
2:27:41baby's out the umbilical cord will be
2:27:43cut in young uh
2:27:48my mic is off
2:27:52right
2:27:54no right
2:27:58okay
2:28:00uh so you can you have seen light very
2:28:02Fresh babies like they have a clip here
2:28:05that is to sort of uh the clip uh
2:28:09the umbilical cord that has been cut
2:28:12right and the uterus so the placenta
2:28:15will also be delivered. So these are the
2:28:17three steps right
2:28:19parturation or the child birth uh close
2:28:23to
2:28:24child birth head of the fetus in the
2:28:26uterus turns towards vagina after
2:28:28completion for development uh 280 days.
2:28:33Okay, fill in the blanks
2:28:37on why do we have uterus uterine wall?
2:28:40Why is the uterine wall composed of
2:28:42muscles to push the baby out? To push
2:28:45the baby out. Okay.
2:28:50Further contraction of the uterine wall
2:28:51disconnects the placenta and associated
2:28:53tissues and the umbilical cord is cut
2:28:56and tied. Right? Ambilical cord is cut
2:28:59and tied from the mother baby's side. It
2:29:02is cut and there's a det.
2:29:05Okay.
2:29:14Okay. Right.
2:29:21Finally, we come to the last part of uh
2:29:24human reproduction. Right. Finally, we
2:29:26come to the last part of human
2:29:27reproduction.
2:29:29Sexually transmitted diseases. Right.
2:29:32I'm not going to go through a lot here
2:29:34because uh most of these are just you
2:29:37can read and understand.
2:29:40What is the bacteria? Gonora is a
2:29:42bacterial disease. Gonora is a bacterial
2:29:44disease caused by
2:29:48MCQ right Neria when you're writing in
2:29:51the CQ be very careful when you write
2:29:53scientific names. Neria simple Gono
2:30:00Ho I right there's a lot of vowels Neria
2:30:04gonor
2:30:06right there are some classic signs of uh
2:30:11gonora maybe there there can be uh
2:30:15absess secretions
2:30:18and if the mother has gonora when she
2:30:21got pregnant
2:30:23the baby can get what we call as the eye
2:30:26infection gonoral eye infection
2:30:28conjunctivitis which can cause blindness
2:30:32these are drawings don't be bothered
2:30:34okay these are drawings
2:30:38otherwise your parents think I'll be I'm
2:30:40sending right
2:30:43uh it can cause blindness and lameness
2:30:45lameness means it can cause uh gonoral
2:30:48sort of affects bones right
2:30:53lameness can lame
2:31:01What do you call lame? There's another
2:31:03name for lame in English. Uh
2:31:07can't walk properly. No lame. Right.
2:31:11Cphillis. Cphilis is also a bacterial
2:31:13disease. These are these will be
2:31:15questioned with bacterial or viral.
2:31:19tropona
2:31:21palidium syphilis
2:31:26I forgot one thing to do this is a
2:31:28scientific name underline
2:31:32if you're writing a scientific name
2:31:34underline troponima paladium underline
2:31:38herpes
2:31:41herpes it's also a species name herpes
2:31:43simplex
2:31:46herpes is a family of viruses genital
2:31:49herpes
2:31:50right
2:31:52genital herpes is caused by herpes
2:31:54simplex
2:31:59right I'm just additional right
2:32:03chicken right chicken pox okay
2:32:09is also a
2:32:11herpes virus but herpes simplex is the
2:32:15genital sexually transmitted herpes
2:32:19Okay.
2:32:24Online people online. Everyone is
2:32:26online, right? Uh
2:32:28no.
2:32:32Great. Okay. What is happening in the
2:32:34chat?
2:32:40Right. Please don't spam the chat. Okay.
2:32:42Right. Otherwise people people's
2:32:43questions will go unnoticed by me. Okay.
2:32:47Okay. Right. It's your responsibility.
2:32:49Uh right.
2:32:51Okay. Herpes simplex is can affect the
2:32:54nervous system. Right. Uh can affect the
2:32:58nervous system. Right. Usually all
2:33:00herpes viruses can affect the nervous
2:33:02system.
2:33:04Particularly when you get chickenpox uh
2:33:06again, right? When you get chickenpox
2:33:09again, when you are as an adult, you can
2:33:12get some uh nervous system problems,
2:33:16right? It can cause permanent
2:33:17disability. Okay. It can cause permanent
2:33:19disability. It can go to the baby as
2:33:21well. Right? Several problems.
2:33:24HIV is caused. Sorry. AIDS is caused by
2:33:29HIV human
2:33:31immuno deficiency virus.
2:33:36Right.
2:33:39uh this AIDS
2:33:43human immunino deficiency syndrome is
2:33:46actually
2:33:48the latest stage
2:33:50of HIV infection
2:33:53right so as they say you get AIDS
2:33:592 to 15 years after HIV infection
2:34:05only so a person who just got this
2:34:08infection you don't call
2:34:12as having AIDS
2:34:15to call a person as having AIDS they
2:34:19must have at least have it for two years
2:34:23right I mean and also they should have
2:34:25the
2:34:27classical symptoms of AIDS what are the
2:34:30symptoms
2:34:32they are immune system is affected okay
2:34:35usually HIV affects immunity. Yeah.
2:34:39Immune system. So HIV infected or AIDS
2:34:45people who have AIDS they have very weak
2:34:48immunity. They have very weak immunity.
2:34:50Therefore for example imagine you get a
2:34:53sore throat right? Sore throat
2:34:56from someone who was having a sore
2:34:58throat. Right? But because you don't you
2:35:01have a nice immune system, you're not
2:35:03going to get pneumonia
2:35:06with the that small infection. But if
2:35:09you have someone that is having immuno
2:35:11deficiency syndrome, that can develop
2:35:14into pneumonia that can go into
2:35:16respiratory distress and they can die
2:35:18from that. Right? But there are now
2:35:22treatments. Now you can be completely I
2:35:26mean almost
2:35:28healthy with AIDS.
2:35:33You can be almost healthy with AIDS.
2:35:35There are drugs for HIV, right? There
2:35:38are drugs for HIV. So the best thing is
2:35:42to get tested and also get treatment.
2:35:46Okay. So that with that with the that is
2:35:50the end of um
2:35:56the
2:35:58human reproduction parts, right?
2:36:03Any questions you have?
2:36:06Do you have any questions?
2:36:13Do you have any questions?
2:36:15I think before we go to uh plant
2:36:18reproduction
2:36:21um I think I should uh finish the
2:36:24genetics part. What do you think? I
2:36:27think I should finish the genetics part.
2:36:30What do you think?
2:36:32Otherwise uh
2:36:34I think that is more important. Right?
2:36:36Because it's almost 8:00 p.m.
2:36:43Right. I think uh we better jump to
2:36:46genetics.
2:36:48What do you think? Send me in the chat.
2:36:50What do you think? Shall we move on to
2:36:53genetics and uh post with the
2:36:56reproduction? Yeah.
2:37:01Right. Inheritance. Okay. Right.
2:37:05So,
2:37:07inheritance is in uh page number 170.
2:37:12Okay. Textbook
2:37:14textbooks right textbooks
2:37:17page number 70
2:37:20sorry 169
2:37:23onwards.
2:37:25Okay.
2:37:38Right?
2:37:46So, ignoreign,
2:37:48ignore all the first few pages, right?
2:37:51Ignore all these first few pages.
2:37:53The body of features of every human is
2:37:55not familiar, blah blah, different
2:37:58colors and these are all there's no time
2:38:02for us to go through,
2:38:04right? So different skin tone ability to
2:38:08roll the tongue. Can you roll the
2:38:09tongue?
2:38:11It's a ability to inherit genetically.
2:38:14Yeah.
2:38:16Right. Some people have the gene that
2:38:19gives them the ability to roll the
2:38:21tongue. Others don't have it. Dimples in
2:38:24the skin, sorry, in the cheek. That is
2:38:27actually dimples in the cheek. Do you
2:38:30know it's a defect?
2:38:32Dimples in the cheek. It's a defect.
2:38:35There's a muscle that is too short here.
2:38:39Okay? That's why you get dimples.
2:38:41It's a defect. Something wrong, right?
2:38:45There's a muscle that is too short. So
2:38:47when that muscle is contracting, it is
2:38:49actually pulling on the skin.
2:38:52It's pulling the skin. So the skin goes
2:38:55inside.
2:38:57Pimples is due to pimples have multiple
2:39:00reasons. Pimples are due to your skin
2:39:03getting infected, right? The pores in
2:39:05your skin getting infected, right?
2:39:07Bacteria getting in there, right? And
2:39:11also some hormones people uh due to
2:39:15hormones some people are more
2:39:16susceptible to get pimples. But that's
2:39:19because when you have too much oily
2:39:20skin, your the pores get blocked. So
2:39:23with that oil bacteria in your skin
2:39:26surface go into the into the pores and
2:39:30there is an infection.
2:39:32Okay.
2:39:34Dimples is a different thing.
2:39:37And also this is called hitchhiker's
2:39:40thumb. If you are if you fully extend
2:39:42your thumb if it's straight that is
2:39:45called straight thumb. This is curved
2:39:46thumb. So I have curved thumbs. Then
2:39:49widow's peak. I don't have widows peak
2:39:52right? that is like this pointed
2:39:54hairline. All those are genetics. Right?
2:39:57Ignore all those. I want you to come to
2:40:01Mendel's experiments page number 174.
2:40:05Mendelian genetics. Right? So, Gregor
2:40:08Mendel was actually a Catholic priest,
2:40:10right? He's known as the father of
2:40:12genetics. He was a very very smart
2:40:14person. Right? In A levels, you will
2:40:16learn very deeply about Mendelian
2:40:18genetics, right? Because when Mendel did
2:40:22these genetic experiments, there was no
2:40:25understanding about anything, right?
2:40:28There were no microscopes. There were no
2:40:31even people even didn't know about DNA.
2:40:34People didn't know about the nucleus
2:40:36inside the cell. Nothing was known when
2:40:39Mendel did these experiments.
2:40:42So that's because of that reason Menel
2:40:46is very very respected because he
2:40:49discovered all these things without the
2:40:51core knowledge. He didn't know anything
2:40:53but he did experiments. He
2:40:57chose a very specific species of
2:41:01organism that is actually a plant to do
2:41:04his experiments. What is it?
2:41:08Garden P.
2:41:10Right. They can ask you in the paper
2:41:14sat.
2:41:20They can ask you in the structure paper
2:41:22what are the why did he choose garden
2:41:25peas can be easily grown can obtain the
2:41:28yield within a short period can obtain
2:41:31pure breeding. What you mean by pure
2:41:33breeding is
2:41:35for several generations over and over
2:41:38you cross the same plant again and
2:41:41again. Right? That means you don't allow
2:41:45any other plant to mix with the plants
2:41:48that you have right now.
2:41:51Right? That is called pure breeding.
2:41:54It's very easy to pure breed pea plants
2:41:57because you can keep them inside
2:42:00green houses. You can keep them inside
2:42:03green houses and protect them from other
2:42:07garden piece. Okay. Easily observable
2:42:10contrasting characters. This is very
2:42:12important. Okay. Pay attention. Okay.
2:42:14Pay attention. Right.
2:42:17What are contrasting characters?
2:42:20I have given here what Mendel used as
2:42:24the contrasting characters
2:42:28right it's a bit blurry you know right
2:42:30but I hope your attitudes are better
2:42:32right he used some contrasting
2:42:35characters
2:42:37what are they contrasting means you
2:42:40should be able to clearly differentiate
2:42:44purple and light purple it's very hard
2:42:47to differentiate but purple and white is
2:42:49Very easy to differentiate yellow and
2:42:53green. Yes, very good. You can clearly
2:42:55see this seed is yellow. This seed is
2:42:57green. Then uh flower position, right?
2:43:00If the flower is on the side or on the
2:43:02top, if the stem is tall, if the stem is
2:43:06short, those contrasting traits that is
2:43:08very important,
2:43:11right?
2:43:13That's one of the features.
2:43:16Naturally self-pollinating when
2:43:18necessary crosspollination also possible
2:43:20okay other mommy uran I'll teach what is
2:43:22self and crosspollination as well right
2:43:25even if you have to stay after 9 okay
2:43:30right so that's these are the reasons
2:43:33these are the reasons why menal chose
2:43:36garden piece
2:43:38right menal chose pam sativ
2:43:41for his experiments okay right
2:43:45Pay attention. Okay. Don't fall asleep.
2:43:47Only two weeks left. Only two weeks
2:43:49left.
2:43:51Okay.
2:43:55Okay. So, Mendel did his experiments
2:43:59like this. So, one of the most famous
2:44:01experiments of Mendel was to cross
2:44:05purple
2:44:06flowers. Pure breeding. Pure breeding
2:44:09purple flowers with whites.
2:44:14This is one of the most famous
2:44:16experiments famous experiments done by
2:44:18men. So how he did it was he took some
2:44:21uh male uh pollen from the white flowers
2:44:26and put them on the female parts of the
2:44:29purple flower and he got this sort of
2:44:32seeds and then he planted the seeds then
2:44:35he waited until he got the flowers
2:44:36again. Right? That's how Mendel did the
2:44:39experiments.
2:44:41So Mendel did this experiment. He
2:44:44crossed purple with white.
2:44:47Okay. He crossed pure breeding purples
2:44:51with pure breeding whites.
2:44:55So what happened?
2:44:57This is the P generation or he parental
2:45:00generation.
2:45:02Pay attention, right? Genetics. Okay.
2:45:05Then he got So he crossed purples with
2:45:08whites. So, how many times did you think
2:45:10he crossed?
2:45:13Did he cross only one purple flower with
2:45:16only one white flower? No. Can you see
2:45:20there's a number here?
2:45:24Read 705 to 224.
2:45:28He cost almost 900 flowers.
2:45:34He crossed crossed almost 900. Okay,
2:45:38I'll disable the chat.
2:45:43Okay,
2:45:54you can ask questions afterwards. Okay.
2:46:09So
2:46:11Mendel did this crossing for almost 900
2:46:15flowers. That's how he did genetic
2:46:17experiments, right? With for genetics,
2:46:20you cannot do only one crossing and stop
2:46:23there because genetics is a probability
2:46:26probability science. It's a law. It's a
2:46:28science that is based on probability,
2:46:31right? cross you're not going to get
2:46:33results. Right? So what happened was he
2:46:37crossed almost 900 flowers and for the
2:46:40first generation he got all purples.
2:46:45Then what he did was he crossed within
2:46:49these purples.
2:46:51He did cross fertilization self
2:46:53fertilization
2:46:54he did. Then he got what? He got 75
2:46:59purple and 224
2:47:02white.
2:47:03>> Oh. Now what happened? He got some
2:47:06whites and he got a lot of purples.
2:47:10If you take this as a ratio, this is
2:47:12almost if you multiply this by three,
2:47:14you are going to get something 700 close
2:47:16to 700. This is very close to the ratio
2:47:203 is to 1.
2:47:24Is very close to the ratio 3 is to1.
2:47:27Okay.
2:47:33Is very close to the ratio 3 is to1.
2:47:37So menal wanted to see why in this uh
2:47:41first generation there was all purple
2:47:43and the second generation he got this 3
2:47:46is to1 ratio. He wanted to know what's
2:47:48the problem. I mean what's the reason?
2:47:52So with that knowledge let's move on to
2:47:55how actually
2:48:00characters are determined. How using
2:48:03what is a gene and how those genes
2:48:07decide what a organism looks like or
2:48:09behaves like. Right.
2:48:13He can Mendel said that features of an
2:48:16organism are determined by a special
2:48:19factors right those factors right he
2:48:22said he didn't know anything right he
2:48:25didn't know anything about what Mendel
2:48:29didn't know anything about DNA right
2:48:32Mendel didn't know anything about DNA
2:48:34but now we know what our characters are
2:48:39determined by the information in our DNA
2:48:42A deoxy ribboucleic acid right Mendel
2:48:48didn't know about DNA but he thought
2:48:50there is something we get from our
2:48:53parents that is going to determine how
2:48:55the children look like he only knew that
2:48:59he thought hurry in the pea plant these
2:49:03parents give these children or offspring
2:49:07something that is going to determine
2:49:09their flower color. So that's how he did
2:49:13his experiments,
2:49:15right?
2:49:17Okay.
2:49:20So to understand that we have to go a
2:49:23bit here right here, right?
2:49:25Deoxxyribboucleic acid present in
2:49:27chromosomes. Chromosomes are found where
2:49:30in the nucleus
2:49:34acts as the genetic material that
2:49:36transmits features of organism from
2:49:38generation to generation. So from your
2:49:41father or your mother how you received
2:49:44information is through DNA is through
2:49:48DNA in the nucleus. Okay.
2:50:04Okay.
2:50:09So uh if you talk if you want to talk
2:50:12about the double helical structure of
2:50:14DNA I'll show you a bit those DNA for
2:50:17sticks covered by two science is called
2:50:19actually Watson Creek and uh sorry uh
2:50:23James Wat James Creek and France wait
2:50:27and
2:50:30right
2:50:31and Francis Creek I think James Watson
2:50:34and Francis Creek right Watson and Creek
2:50:37right I'll show
2:50:39how DNA is like but I think it's not in
2:50:42your syllabus a little bit right
2:50:49it's not exactly in your syllabus but uh
2:50:59right but it's important for your high
2:51:01level life that you know what a DNA is
2:51:04like
2:51:07Right? If you take
2:51:10DNA,
2:51:15it's like this. It's like a it's like a
2:51:18staircase. Spiral staircase
2:51:21DNA, right? DNA is like a spiral
2:51:24staircase,
2:51:26right? That is going to hold all this
2:51:29information. And it is actually composed
2:51:31of this sort of four types of chemicals
2:51:34that are called nucleic acids that are
2:51:39in this sort of helical shape. It's like
2:51:41a spiral stage. So it's going to compact
2:51:45itself pack itself into this structure
2:51:49called the chromosome. Right? These are
2:51:52called chromosomes or
2:51:54because why do we need chromosomes is
2:51:57that we have so much DNA in in a cell.
2:52:00If you take one of my cells from my body
2:52:03inside that there is so much DNA right
2:52:06it's there's a very large very long this
2:52:09length of DNA molecule the thing is the
2:52:12cell is very small there's a lot of DNA
2:52:14so the best thing is to do what to pack
2:52:18this DNA
2:52:20tightly
2:52:22tightly pack into a structure that we
2:52:26call as the chromosome
2:52:29chromosome
2:52:32These chromosomes contain so much
2:52:35information, right? These chromosomes
2:52:37contain so much information.
2:52:42Yes. Uh that's all I wanted to show you.
2:52:47Right. So this is again something the
2:52:50this is how DNA is composed of. If you
2:52:53go to molecular level, right?
2:52:57This is that spiral staircase. Right.
2:53:01Double helix. We call it a double helix.
2:53:04Okay.
2:53:09Right.
2:53:13Okay. Come back down. Right. Then we
2:53:17move on to something called
2:53:22homologus chromosomes. Right. So it's a
2:53:26nice concept that I want you to
2:53:27understand right. I hope uh did you did
2:53:30you learn this when you are learning
2:53:33this uh homologous sorry when you are
2:53:36doing inheritance did you learn about
2:53:38these things?
2:53:42So if you think about how you were
2:53:46produced, right?
2:53:48Father
2:53:49gave the sperm,
2:53:52made mother gave the egg,
2:53:56right? Mother
2:53:59gave you half of the DNA you have.
2:54:03Mother gave you half of the DNA that you
2:54:05have. Father gave you half of the DNA
2:54:08that you have. So if you are a human how
2:54:12many chromosomes do you have? I have
2:54:16given here. How many chromosomes do you
2:54:19have? It actually changes from different
2:54:22species to species. They say uh mouse
2:54:26has 40, chimpanzeee has 48,
2:54:30patty has 24, cop has 104. Humans we
2:54:34have 46.
2:54:37We say 23 pairs.
2:54:41You can see here here right there's 23
2:54:43pairs.
2:54:46These are sex chromes. Okay. So half
2:54:50came from your father half came from
2:54:53your mother. So actually if you take two
2:54:57of these these are can you see these are
2:54:59connected right these are closely
2:55:01associated so I'll say this one of these
2:55:05pairs came from the father one came from
2:55:08the mother so if you are a human
2:55:12you got 23 chromosomes from the mother
2:55:16you got 23 from the father
2:55:22right and An important nice thing is
2:55:26they are sort of structurally similar.
2:55:30They look similar, right? The mother and
2:55:34the father, the chromosomes that they
2:55:36gave you, if you nicely
2:55:38match them up, if you pair them up, you
2:55:41can pair them according to their
2:55:44appearance. So the the biggest two like
2:55:47this, you can arrange the biggest two
2:55:50like this. Sorry.
2:55:53You can arrange the biggest two like
2:55:55this. Then the next biggest two like
2:55:58this. Right?
2:56:00You can arrange these 23 and 23 from
2:56:03your mother and father into what we call
2:56:06as homologous pairs.
2:56:10If you take a homologous pair, one came
2:56:13from the male, one came from the female.
2:56:15So here this is tag this is ammon
2:56:21but you have both right and if you take
2:56:24a closer look they contain the genes
2:56:28right genes
2:56:32in your chromosome they are our genes
2:56:35genes do what? Genes determine
2:56:38characters. Genes determine characters,
2:56:44right? For example, your skin tone, your
2:56:48intelligence, your height, ability to
2:56:50roll your tongue, your eye color, hair
2:56:52color, hair type, straight to wavy,
2:56:55whatever will be decided by the genes in
2:56:58this chromosomes.
2:57:01Okay?
2:57:04Right? So with this understanding we can
2:57:08come to this next concept that is called
2:57:13homologous I'm sorry homozygous and
2:57:16hetererozygous.
2:57:19What do you mean by homozygous?
2:57:30Homozygous means for example
2:57:32if you go to this homologous chromosome
2:57:34can you see here there is capital A and
2:57:37capital A that means the two genes are
2:57:41the same right I'm not going to use the
2:57:44uh there's this is not the proper word
2:57:47the proper word is not gene the proper
2:57:49word is not gene right but it's in your
2:57:52syllabus that's what I'm going to use
2:57:55the proper word is al but I'm not going
2:57:56to use it right you can see the two
2:57:59genes are same. No, capital A and
2:58:01capital A. That means what? In both
2:58:03homologous. So from your mother and
2:58:05father chromosomes, they are the same.
2:58:08That means that is a homologous
2:58:12pair. Right? So what is the definition
2:58:15of homologous? I'm sorry. I'm sorry.
2:58:17Homozygous.
2:58:21What is the definition? If two genes
2:58:31are similar
2:58:36for a given
2:58:40feature
2:58:42then you can say it's a homozygous
2:58:46condition.
2:58:48Then if you go down to this diagram
2:58:50again
2:58:52you will see methanine there's a simple
2:58:54C and a capital C that means what? They
2:58:59are not the same.
2:59:01They are not the same. So if you have
2:59:04two if the genes are not similar you
2:59:08call it hetereroy. If two genes
2:59:13are not
2:59:16similar then it's called heterrozy.
2:59:21Okay. Then there are something I want
2:59:24you to know that is called dominant
2:59:30versus recessive genes.
2:59:35What do you call dominant process
2:59:36recessive means when you have two genes
2:59:40in this hetererozygous condition
2:59:43gene makeup is the loca one gene is more
2:59:49powerful than the other gene
2:59:52right one gene can be more powerful than
2:59:55the other gene
2:59:59that gene is called the dominant more
3:00:02powerful than the other gene that gene
3:00:05is called the dominant gene.
3:00:07Right? So if you take this homozygous
3:00:12condition for this purple, can you see
3:00:17purple?
3:00:18Let's say this purple color. I have
3:00:21included a diagram I think.
3:00:26Yes. Uh here can you see?
3:00:30Right.
3:00:34See
3:00:36this gene sorry this chromosome is
3:00:39father's this chromosome is mothers blue
3:00:42father
3:00:45this is the gene
3:00:48gene when we magnify it's actually DNA
3:00:50so this is the gene when you magnify
3:00:53that gene you have
3:00:56DNA so what that DNA is going to do is
3:00:59actually code for some enzyme enmes it's
3:01:02going to p for some enzymes. That enzyme
3:01:05is going to produce the purple color.
3:01:07That's how you get purple color. That's
3:01:10similarly for us also. That's how you
3:01:12get your skin color. Skin color is due
3:01:14to a pigment called melanin. If you have
3:01:17the chemicals to make this melanin a
3:01:21lot, that means your skin color is going
3:01:23to be dark. If you don't have a lot of
3:01:27melanin, that means your skin color is
3:01:29going to be light, right?
3:01:32So that's the same for purple color.
3:01:36So
3:01:39in this example, this purple color
3:01:43determining gene,
3:01:45purple
3:01:47color determining gene is dominant.
3:01:53coloring gene is dominant. So what's
3:01:56going to happen? If you listen very very
3:01:58carefully right what's going to happen
3:02:01is listen very very carefully
3:02:05in this condition where the two genes
3:02:08are not same P capital P and simple P
3:02:12valve who is the loca who is the leader
3:02:16who is the most powerful capital P
3:02:20therefore this simple P will be ignored
3:02:23this simple P will be ignored So purple
3:02:27color will be produced.
3:02:30Purple color will be produced. What is
3:02:33the only situation that simple P can
3:02:37work? Simple P causes what?
3:02:41Simple P causes white color.
3:02:44What is the only time simple P can work
3:02:47is when he's alone. Only simple P simple
3:02:51P without any capital P. If simple P is
3:02:55there then he can do his thing. But if
3:02:59there is at least one capital P then the
3:03:04simple P is what? Powerless very weak.
3:03:08That's why we say
3:03:11if you have capital B capital P yes
3:03:14purple.
3:03:15If you have capital P simple P also
3:03:18purple capital P simple P purple but if
3:03:22you have simple P simple P then only
3:03:24white.
3:03:27Okay then only white
3:03:40then only bite. Can you understand? Can
3:03:43you understand what is dominant and
3:03:44recessive? It's actually powerful and
3:03:47powerless. Okay,
3:03:54I have enabled your chats again so you
3:03:57can ask any question.
3:04:04Okay. If you have any questions, you can
3:04:06ask them.
3:04:07Okay. Right.
3:04:16Okay, I'll come to monohybrid pro. Don't
3:04:18worry may basic understand you cannot
3:04:21come to crossing.
3:04:23Okay, now clear how what is a homologus
3:04:28pair? How your mother and father gives
3:04:30you chromosomes, right? Meiosis,
3:04:33right? I included a small diagram of
3:04:35meiosis, right? Just to for you to
3:04:38remember, right? meiosis. This is what a
3:04:41gene looks like, right? It's a piece of
3:04:44DNA that is going to determine a certain
3:04:46feature, right? So
3:04:50that's how you get different features.
3:04:52There are genes that are dominant. There
3:04:54are genes that are recessive. For the
3:04:56recessive gene to work, what is the only
3:04:59place? You have to be recessive
3:05:02homozygous. Otherwise, the recessive
3:05:04gene is always masked,
3:05:08hidden.
3:05:09Right. So I'll come to introduce these
3:05:13two terms. Now what is a phenotype? What
3:05:17is a genotype?
3:05:19The feature that externally appears is
3:05:21known as
3:05:24phenotype. Elliot P is the phenotype.
3:05:28But inside if you take the cells the
3:05:31genetic composition is known as the
3:05:33gene.
3:05:35Right? You have to fill these. Huh?
3:05:38So what can you see? Genotype is not
3:05:41always same as phenotype. Can you
3:05:43understand?
3:05:46Because why?
3:05:52To the outside you can see purple purple
3:05:55purple purple
3:05:57right you from the outside you see
3:06:00purple purple purple purple purple. But
3:06:02if you go and look at the genes, you'll
3:06:05see that their genotypes are different.
3:06:08It can be capital P, capital P, capital
3:06:10P, simple B, capital P simple.
3:06:13So the phenotypes can be different from
3:06:15genotypes. Understood?
3:06:19Right? Phenotypes can be different from
3:06:21genotypes. So with that basic concept,
3:06:26so can you understand your resource? I
3:06:28mean your textbook is I don't know it
3:06:32should be revised right now it's too
3:06:35late but can you understand whenever
3:06:39they start with the deep stuff and then
3:06:41come to the basic concepts right it's
3:06:43not the proper way right I hope you were
3:06:46taught that way but never mind but
3:06:49understand with me now right so now we
3:06:53come to this what happened here
3:06:58Why did we get this 3 into one ratio?
3:07:02For that we need what
3:07:06that understand. So let's go to the
3:07:08whiteboard and draw
3:07:12this monohybrid cross right.
3:07:29Menal monohybrid crossing. How did he
3:07:32what did he do? He crossed
3:07:36purple
3:07:39pure breeding purples with
3:07:43white.
3:07:48He cross pure breeding purple with
3:07:49white.
3:07:51Right?
3:07:53This generation is known as
3:07:58sorry is known as
3:08:01parental generation. Right? These are
3:08:03the parents.
3:08:05He crossed the parents.
3:08:08So these are pure breeding parents. So
3:08:12now tell me if someone is pure breeding
3:08:17what are the genes that he can have?
3:08:20Pure breeding. Now that means what? He
3:08:24has to be dominant. He has to be
3:08:28dominant homozygous. He has to be
3:08:31dominant homozygous. That means what?
3:08:34Capital P. Capital P.
3:08:39If he is white, then what is the only
3:08:42possibility of genotype that is have?
3:08:45Simple P. Simple
3:08:50ne
3:08:52then what are the gamts that they can
3:08:55produce?
3:08:57What are the gamts that they can
3:08:59produce?
3:09:03What are the gamts that this
3:09:08purple can produce? He can only produce
3:09:12what? He can only produce
3:09:15capital P. He can only produce capital
3:09:19P. What can the simple B produce? He can
3:09:23only produce simple P. Then
3:09:28so now what we are going to do is we are
3:09:31going to
3:09:33cross them.
3:09:36We going to cross them.
3:09:40Right. We are going to do a nice
3:09:42crossing experiment main.
3:09:45What you are going to obtain is the F1
3:09:47generation. So what is
3:09:51the genotype of the F1 generation? What
3:09:53is the genotype of the F1 generation? It
3:09:56is capital P simple. P capital P simple.
3:10:01So what is going to be the outer
3:10:05let's say the output or let's say the
3:10:09genotype
3:10:11they are purple
3:10:13because why this capital P is dominant
3:10:17this capital P is dominant
3:10:20right
3:10:23then what are we going to do is we are
3:10:25going to cross f_sub_1 with f_sub_1
3:10:32we are going to cross fertilize these F1
3:10:35people. So to visualize that we are
3:10:38going to draw something that was
3:10:40introduced by a scientist called
3:10:44scientist.
3:10:46Okay that is
3:10:50to do what? We are going to draw a
3:10:53square. We are going to draw a panut
3:10:56square.
3:10:58Panut square. So
3:11:01usually there's a male plant and a
3:11:03female
3:11:05sperm egg.
3:11:08Right? So what are the sperms that can
3:11:12be produced? What are the sperms that
3:11:14can be produced?
3:11:16They can produce simple P sperm and
3:11:20capital P sperm. this side also they can
3:11:23produce capital piece perman
3:11:27right
3:11:36you understood right this F1 generation
3:11:39can only produce can produce both no
3:11:43this F1 generation can produce both
3:11:46capital P and simple P gamX got it so
3:11:50what are going to be the possible
3:11:52outcomes, right?
3:11:54Capital P, sorry, capital P, capital P,
3:11:58capital P, simple P, capital P, simple
3:12:01P, simple P, simple,
3:12:06right? Then what is tell me
3:12:10right? How do they look like to the
3:12:12outside? Purple
3:12:15milk. Purple
3:12:18purple purple
3:12:20only one white.
3:12:27So
3:12:29tell me what is the ratio? Phenotypic
3:12:33ratio.
3:12:35Penotypic ratio, flower color ratio,
3:12:39purple to white ratio is what?
3:12:453 is to 1.
3:12:56Phenotypic ratio is 3 is to1.
3:13:04Okay,
3:13:07ratio is 3 to one.
3:13:11We'll explain again. I'll explain again.
3:13:14Right. This is not the example that you
3:13:16have in the uh text.
3:13:22So what we are going to do is right.
3:13:24Okay. Listen listen.
3:13:28We have
3:13:30two generations
3:13:32of flowers.
3:13:36One is one are purple, one are white.
3:13:38Right? So for sure we know these purple
3:13:43are having capital P capital P because
3:13:45why capital P? Capital P is the gene
3:13:49that is going to produce the purple
3:13:51color. Right? Capital P.
3:13:55Capital P produces purple. Simple
3:14:02Ping here is going to produce white
3:14:07but he's going to be almost always
3:14:10masked by the capital P.
3:14:13So if you take this capital P capital P
3:14:18purple what is the only type of gamt he
3:14:21can make because he has no other option
3:14:24he has only capital P genes so he is
3:14:27going to give capital P genes this one
3:14:29only has simple P so he's going to give
3:14:31simple P genes then we are going to
3:14:33cross then what are you going to get you
3:14:36going to get this F1 and I forgot to
3:14:39mention this F1 generation monohybrids
3:14:46Who are these monohybrids?
3:14:49Monohy
3:14:50F1
3:14:53monohybrid.
3:14:55Why do we call it monohybrid?
3:14:58Because can you see there is one capital
3:15:02or dominant there is one recessive.
3:15:06So
3:15:08it's a half and half mono hybrid right
3:15:13there is one hybrid
3:15:19right.
3:15:22So if you take
3:15:24capital T simple T capital P simple
3:15:28short
3:15:30dihydrates. So do you have dihybrids in
3:15:33A levels?
3:15:35In O levels you only have monohybrids.
3:15:37Then what we are going to do is we are
3:15:39going to cross the monohybrids with each
3:15:41other. We are going to cross the
3:15:42monohybrids with each other.
3:15:45Then you are going to draw this pan
3:15:47square. And in the pan square you are
3:15:49going to get capital P capital P.
3:15:52Capital P simple Purple
3:15:55capital P simple P again purple but
3:15:58simple P simple P it's going to be
3:16:00white. So purple to white ratio is 3 is
3:16:03to1.
3:16:04Purple to white ratio is 3 is to1.
3:16:08Okay. I know it's difficult but we have
3:16:11completed genetics.
3:16:14Got it.
3:16:22Right.
3:16:25Yes. I'll send the recording up. Okay.
3:16:27But uh if you can keep keep uh I mean
3:16:32keep watching the live recording. Okay.
3:16:33Live sorry live stream. Got it. Let's go
3:16:37back to the tote.
3:16:43So this is how we explain why Mendel got
3:16:47705 purple flowers and why Menel got
3:16:51only sorry why Menel got 705 purple
3:16:54flowers and why he got 224 white flowers
3:16:58that is because of what dominant and
3:17:01recessive monohybrid. So this is the
3:17:03hybrid that we crossed and we got 3 is
3:17:08to1 ratio
3:17:12of
3:17:15uh flower color in the
3:17:18F2 generation. Got it?
3:17:23Then we come to that is the end of
3:17:25Mandelian genetics.
3:17:28Right? He me what Mendel mentioned was
3:17:31only those two right
3:17:36then human sex determination is interest
3:17:38right human sex determination you have
3:17:40to have this idea here
3:17:46these two X and Y that's what we need to
3:17:50understand human sex determination
3:17:54right that's why we need to understand
3:17:56human sex determination
3:17:58We have what we call as
3:18:0223 autosomal chromosomes
3:18:06autotosomal kanti that are not related
3:18:09to sex. Then we have one pair of sex
3:18:14chromos. So one pair these are 23 pairs
3:18:17of pairs
3:18:22right? If you take a girl, female, they
3:18:25are going to have these two chromosomes
3:18:28that are called the X chromosomes X and
3:18:31X. If you take a man, he is going to
3:18:33have X and Y.
3:18:36So if
3:18:40you want boy, what is the combination
3:18:43that you need? Your mother can only
3:18:47produce X because why? She only has X.
3:18:50Your mother can only produce X
3:18:53chromosomes because only X. Your father
3:18:56can produce both because he has X and Y
3:19:00both. So if you are having if you are a
3:19:03girl born to your parents that means
3:19:06what? Your mother gave X. Your father
3:19:08also gave X. So you became a girl.
3:19:13If you are a boy then your mother gave X
3:19:16because he has no other option. But your
3:19:18father gave you a wife. So you ca you
3:19:21became a boy,
3:19:25right? That's why you became a boy. So
3:19:28who is the most who is this most
3:19:29powerful chromosome? That is the what?
3:19:39Right. This Y chromosome is very I mean
3:19:42it can decide if you are a male or a
3:19:45female. Very small. Right? Now can you
3:19:49see these X chromosomes are almost the
3:19:52same length. So we can call them as
3:19:55homologous.
3:19:57They are homologous to each other. Can
3:19:59they are matching not?
3:20:01But what can you say about X and Y? They
3:20:05are not matching. You can't pair them
3:20:07up. You can't pair them up nicely
3:20:10because why? The Y is smaller. Y is 2T.
3:20:14Right? Therefore you can't pair them up.
3:20:16That becomes a problem when that becomes
3:20:20a problem when
3:20:23what we come to diseases that are caused
3:20:28by problems in the sex chromosomes.
3:20:32There are diseases that are caused by
3:20:33problems in the sex chromosomes. There
3:20:36can be other diseases that are caused by
3:20:38other chromosomes as well. Then 23,
3:20:42right? There are so many other genetic
3:20:45disorders that are caused by problems in
3:20:48these all the other chromosomes. But
3:20:51something very special happens when you
3:20:53come to this X and Y because why? This Y
3:20:56chromosome is small.
3:21:01Males face more problems. Males face a
3:21:06lot of problems because why the Y
3:21:08chromosome is small? Because it's
3:21:11shorter. Most of the genes are absent in
3:21:14Y. Therefore,
3:21:16for the Xlink genes, there are no
3:21:18complimentary
3:21:22when you have a problem
3:21:24in one of these X chromosomes. For
3:21:27example, imagine methantheino. There's a
3:21:30gene that is coding for the visual
3:21:34pigments in your eye that helps you to
3:21:37see color,
3:21:39right? What are the colors that we see
3:21:41mainly? Right? Our eyes only three red,
3:21:43green and blue. Okay? So using those
3:21:46three colors we can see all the other
3:21:48mixtures of colors. Right? There are
3:21:51sensors in our eye for red, green and
3:21:54blue color. Right?
3:21:57So
3:21:59imagine there's a problem in the gene
3:22:01that is coding for the red and
3:22:05green color in the X chromosome. It's
3:22:07located in the X chromosome.
3:22:09But it's okay in a female because why
3:22:15there's another X chromosome X
3:22:17chromosome there's another X chromosome.
3:22:21Yes. Therefore no problem may
3:22:24problematic gene can be ignored because
3:22:26there's another X chromosome. But come
3:22:28to male.
3:22:31Imagine there's a problem in this X
3:22:32chromosome. There is no such gene in the
3:22:37Y chromosome because why the Y
3:22:40chromosome is too small. Why chromosome
3:22:43make a body ready? So there are no
3:22:46proper genes to cover up the mistake.
3:22:49That's why you are going to get diseases
3:22:51like color blind. Right?
3:22:57Chat is open.
3:23:00You can send messages. Right.
3:23:04What is the number that you can see
3:23:06here?
3:23:12Here is a number you can see here.
3:23:21Can you see a number? Oh, the screen is
3:23:23blurry there.
3:23:29Now the chat is out.
3:23:37Okay.
3:23:40Okay. Tell me what is the number you can
3:23:42see here.
3:23:48Zoom in a bit.
3:23:54What is the number you can see here?
3:23:58Right. I'm I'm doing this free of
3:24:00charge. I'm teaching you science free of
3:24:01charge and I'm doing a I test for you
3:24:03free of charge.
3:24:06Okay,
3:24:07I should start charging. Hurry. What is
3:24:11the number here?
3:24:21You can't see the number.
3:24:31It means you're color blind.
3:24:37It's just a pattern, right? Okay. So,
3:24:40this uh
3:24:43set of charts, this is called
3:24:46uh an Ishihara chart. It's sort of a
3:24:48Japanese scientist that introduced this,
3:24:50right? It's called an Ishihara chart
3:24:52that when you get your license also
3:24:55driving license they are going to give
3:24:58you this Ishihara chart to see what if
3:25:01you can see red and green colors
3:25:06and also blue green blue
3:25:11people can't see the blue color people
3:25:13who have red green color blindness can't
3:25:14see red and green color so if you have a
3:25:17driving license then red green color
3:25:19blind people can't see traffic lights.
3:25:21That's a big problem, right? If you
3:25:24can't see the traffic lights as red or
3:25:26green, then it's a big problem, right?
3:25:35So, you cannot have a license if you are
3:25:39red or green color blind. Right? So
3:25:41color blindness is
3:25:45sex chrom I mean X the gene is located
3:25:49in the X chromosome for red and green
3:25:52pigments
3:25:54the gene is located in the X chromosome
3:25:57it's like this.
3:25:59So the inheritance of this uh color
3:26:02blindness is like this.
3:26:05Imagine
3:26:09there's a mother
3:26:15Okay. Mother is hiding the color blind.
3:26:19No. Uh let's say the mother is healthy.
3:26:24And also remember most of these diseased
3:26:28genes, bad genes are recessive genes.
3:26:31Most of these bad genes are recessive
3:26:33genes. So this mother is healthy. So she
3:26:36has capital C, capital C, good genes.
3:26:40Father is color blind.
3:26:43Father red green. So tell me
3:26:47you don't draw it like this actually.
3:26:53X a K capital C and X a K capital C.
3:26:58This means what? The mother is
3:27:01healthy. Then there's the father who has
3:27:04color blindness. Simple C and capital Y.
3:27:07We don't write anything here because why
3:27:10Y chromosome doesn't have anything. So
3:27:13tell me so mother is healthy,
3:27:17father has color blind.
3:27:23Now tell me what is going to happen to
3:27:25their children?
3:27:28What's going to happen to their
3:27:29children?
3:27:31This mother can produce eggs that are
3:27:34all having this
3:27:38capital C. This father can produce
3:27:41sperms that has X symp
3:28:00X simple C sorry
3:28:03and X capital C and Why?
3:28:10So tell me, are any of these children
3:28:13going to be color blind?
3:28:16Color blindness and all?
3:28:18Sorry.
3:28:21Are any of these children going to be
3:28:23color blind?
3:28:28No.
3:28:31This is what we call as
3:28:34what is the gender of this child? This
3:28:36child is a female
3:28:40X and X but she's healthy.
3:28:47What is the gender of this child? He's a
3:28:49male
3:28:51but he's having what? The nice healthy
3:28:56gene from the mother. So he's also
3:28:59healthy.
3:29:04He's healthy. then healthy both are not
3:29:06going to get color blindness.
3:29:10All right.
3:29:12Okay.
3:29:16As example in your resource which is the
3:29:17other way around. If you have a deceased
3:29:20mother and a healthy father, but even
3:29:25though this mother is we call healthy at
3:29:28this mother is not having color
3:29:30blindness but sorry not mother this girl
3:29:35is not having color blindness but she is
3:29:37a carrier.
3:29:40She's hiding the disease. She's hiding
3:29:43the disease,
3:29:45but she's healthy because she has a good
3:29:47alene.
3:29:50Okay, al comes out, right? She has good
3:29:54genes, therefore she's safe, but she's a
3:29:57carrier.
3:29:58She's a carrier.
3:30:01Okay?
3:30:04Then there are other genes, right? I
3:30:08mean I told you other than the sex
3:30:11chromosome there are so many other
3:30:12chromosomes. So these chromosomes can
3:30:15become damaged. They can change. They
3:30:17can undergo so many problems. So
3:30:23there can be so many other
3:30:25genetic diseases. One example is this
3:30:28albinism. So a person to be albino like
3:30:32this white table like eyebrows hair
3:30:36everything is white.
3:30:37For that you need this simple A simple A
3:30:41combination.
3:30:43If you have capital A capital A that
3:30:45means you are healthy
3:30:48right. But if you have capital A simple
3:30:51A that means you are carrier carrier.
3:30:56Okay. Similarly there's a disease called
3:30:58talismia.
3:31:02Hemoglobin is faulty.
3:31:06Bad hemoglobin molecules are produced.
3:31:08Bad hemoglobin molecules are produced.
3:31:11Therefore,
3:31:13um
3:31:15they have low hemoglobin that is going
3:31:17to cause anemia. Anemia
3:31:22sing that means if you take a full blood
3:31:24count of them, they are going to have
3:31:26low hemoglobin. Even you don't need to
3:31:29take a full blood count, right? They
3:31:31have so many features. They get easily
3:31:33tired. They can't work a lot. They have
3:31:36pale sort of skin, red color,
3:31:40right? If you look under their eyes like
3:31:42this, have you seen doctors when you go
3:31:44to the doctor the one of the first
3:31:46things they do is they look under your
3:31:49sort of eyelid. That is to see if you
3:31:51are anemic. If you have enough blood,
3:31:55right? If you have talismia, you're
3:31:57going to have anemia.
3:31:59Okay.
3:32:02Right. Any questions?
3:32:05We have 15 minutes more. Let's do some
3:32:09questions from uh what we discussed
3:32:12today. Okay.
3:32:15I think uh your attention pan is kind of
3:32:19dropping at this moment, right? So let's
3:32:23do a question and finish for the day.
3:32:26I think I have yes
3:32:33past paper 2021 to 20. Yeah, 2021 past
3:32:37paper I have. I don't know why the
3:32:40quality is so bad.
3:32:43Um I saw some questions that we can do.
3:32:47Did you do you know how you know how I
3:32:50mean out of the 40 MCQs you know about
3:32:5215 to 16 is a bio questions right?
3:32:56Oh, nice, nice, nice.
3:32:59Quickly do this. Question number 15.
3:33:03I'm sorry. Question number 12. Question
3:33:04number 12. Right. I hope you can see.
3:33:08Right. Question number 12.
3:33:12Uh R and S. They're asking what is R and
3:33:17what is S?
3:33:21What is R and what is S? They asking
3:33:36Quickly send me.
3:33:38Quickly send me. What's the answer?
3:33:40Quickly, quickly. Thank you.
3:33:59Quickly, there are almost a lot of
3:34:01people in the group. quickly on if I see
3:34:04anything other than the correct answer
3:34:15is carrier. Yeah, when you don't send to
3:34:17the main chat, I tend to forget.
3:34:21It's free. Yes.
3:34:24Uh I mean it's not a class that I do
3:34:27regularly. I do a level biology. So
3:34:31after your
3:34:33levels you can think about joining my
3:34:35classes right
3:34:41just focus on your olive first. Yes very
3:34:46simple you know R is the uterus S is the
3:34:49vagina label the others. What is Q
3:34:53fallopian tube P ovary.
3:34:57Okay
3:34:58next question. Question number 13,
3:35:01send me the answer. Question number 13,
3:35:03quickly send me the answer.
3:35:36So I will let you know the future
3:35:38updates with the upcoming seminars and
3:35:41everything in the coming in the WhatsApp
3:35:43channel. The recording will be available
3:35:45in the WhatsApp channel. Uh because new
3:35:48people are going to be adding every day.
3:35:51So I can't keep on sending the
3:35:53recording. it will be available in the
3:35:56channel right and uh so yeah I will try
3:36:01to cover the maximum go through the
3:36:03tutorials I have sent right so the
3:36:07second seminar will be from grade 11
3:36:10from your systems okay and fertilize
3:36:14with the sperm where where is
3:36:17fertilization happening
3:36:19in the fallopian tubes okay
3:36:21fertilization is happening in the
3:36:22fallopian tubes Right. Very very
3:36:25important to remember fertilization
3:36:27happens in the fallopian tubes.
3:36:31Right.
3:36:35Um, anything else that we can do?
3:37:04No. Huh. Um
3:37:09gas contributing these are from
3:37:11biosphere
3:37:15anything.
3:37:17Yeah. From plant reproduction. There's
3:37:19something
3:37:22right like I'll do it as much as I pos I
3:37:26can next week. Right. Yeah. Uh nothing
3:37:30much more that we can do in this paper.
3:37:34Right. Uh, anything genetics did you
3:37:36see? Any genetics questions? Do you have
3:37:45this is uh is an alvololis right? Uh we
3:37:49can do that after the next week's uh
3:37:52seminar.
3:37:56So you can see you cannot underestimate
3:37:59right? You cannot underestimate.
3:38:02Okay. So what you can do is join with
3:38:04the next week's class with the next
3:38:07week's seminar and uh
3:38:11get the maximum benefit right get the
3:38:14maximum benefit as much as possible from
3:38:16this free session and I I have some of
3:38:19my colleagues that are some of my
3:38:22colleagues
3:38:24particularly Janit and
3:38:27Chamika those are that are doing this
3:38:31similar
3:38:32seminars for
3:38:37O level people right level students. So
3:38:41try to cover the physics and chemistry
3:38:43from those sort of seminars as well,
3:38:45right? Uh and I think particularly the
3:38:50bio part is more let's say you can get
3:38:53more marks by studying the bio part than
3:38:57compared to physics and chemistry.
3:39:00pass paper discussion session.
3:39:03Okay, sure the time is the issue. If you
3:39:06are able to join
3:39:10um but uh after
3:39:13yeah grade 11 will be next seminar I
3:39:16will let you know right with the demand
3:39:18I think I'll do a pass paper discussion
3:39:20separately right that's uh good for you
3:39:23as well okay
3:39:26yeah so keep in touch share the
3:39:29recordings uh
3:39:31add people to the group
3:39:34yeah we'll finish for the
3:39:38The link will be sent. The link will be
3:39:41sent. I think I I plan to do a YouTube
3:39:43live as well because today there was
3:39:46Yeah, keep studying. Huh? Keep studying
3:39:49and uh after finish this level bar exam
3:39:53it's a just a small barrier just get
3:39:56through it and uh
3:39:59level bioan. Okay. Right. Okay. Thank
3:40:03you for joining. Good night. Okay.
3:40:17Okay. Good night.
3:40:21I'll send the channel link again. Sure.
3:40:25If you're in the WhatsApp group, I'll
3:40:26send Okay.
3:40:34Okay. Mystery seminar is done by pass.
3:40:36Okay, I'll uh send one of his.
3:40:45Sure. Uh send the message people who are
3:40:48not in the group.
3:40:51Send a message to
3:40:56Send a message to 07078
3:41:0266 64.
3:41:06Send a message to this number.
3:41:14Okay.

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