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Lfsc Gr 11 Vrl Prep For Nov Exam 2026 P2 Q3 — Transcript

by Cicilia Van heerden · 4,565 words · 764 segments · language en · Watch on YouTube

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0:00seven.
0:01So,
0:02uh as we start, uh we are having a
0:06population ecology as the first topic
0:08there.
0:09So, on this slide, we are having
0:11population growth forms.
0:13The two population growth forms are our
0:15logistic growth form and our exponential
0:18growth form. The J-shaped one and the
0:21logistic is our S-shaped growth form.
0:24So, here we are having the descriptions
0:27of those two graphs. Uh
0:30our our logistic growth form
0:32uh is the population growth form that
0:34shows slow growth due to reproductive
0:37slow reproductive rate. And uh there's
0:40predation there and there are diseases
0:43or low food supply. So, this is the
0:45phase where there is a very low a slow
0:48growth and then
0:50there can also be limiting factors which
0:53can which can affect the growth
0:54population. So, the limiting factors can
0:57be shortage of food,
0:59water,
1:00shortage uh shelter, predation, or also
1:03diseases. So, the population mostly do
1:06not reach the carrying capacity. So, our
1:09carrying capacity here on this graph is
1:11represented by this red line up there.
1:14So, this is our carrying capacity. The
1:16carrying capacity is uh the number of
1:19maximum number of organisms um the area
1:22or the habitat can carry.
1:25So, uh
1:26organisms in this
1:28uh population cannot reach the carrying
1:30capacity because of these limiting
1:32factors.
1:33So, this graph has four phases.
1:37We know that uh teachers taught our
1:39learners these phases. The four phases
1:41are the first one is the lag phase. The
1:43second one is the exponential phase. The
1:46third um uh decelerating phase or the
1:50death phase. And uh the last one it will
1:53be our equilibrium phase. So, learners
1:56have to know this all these phases. Um
1:59they might be asked to label the phases
2:01on the graph and so on.
2:04Uh, this is our logistic growth form.
2:06And our exponential growth form, the
2:08J-shaped one, the population here grows
2:11exponentially. It grows rapidly fast
2:13because of higher reproductive rate.
2:17Organisms are settled, they can
2:19reproduce, and, uh, limiting factors can
2:22arise. And then when limiting factors
2:24arise in this type of exponential
2:27growth,
2:28they will lead to death or extinction.
2:31And, uh, the population can exceed the
2:33the carrying capacity. It means in this
2:36population in this, uh, type, sorry.
2:38Sorry.
2:40In this type of exponential growth,
2:42it means, um, organisms can, uh, be, uh,
2:47larger or the number of organisms in
2:48this can be larger than the carrying
2:50capacity. So, they they are phases
2:52there. We have the lag phase and the
2:54exponential phase. The last one is the
2:56death or extinction phase. So, that is
2:59our two population growth forms. One of
3:02them will be there in our te- in our
3:05exam.
3:07As we move on, we have factors affecting
3:10the size of the population.
3:12So, these factors are divided into two,
3:15density-dependent factors and
3:17density-independent
3:19factors. So, uh, the density-dependent
3:23factors
3:25uh, are those factors that have
3:27>> [snorts]
3:27>> a direct uh, correlation with the size
3:30of the population. It means the size of
3:33the population is, um, affected affect
3:36this, uh,
3:38I mean, they're affected by the size of
3:39the population. So, examples of them are
3:41the territorial behavior. Organisms can
3:44fight in, uh, for territory or for for
3:47the space. And predation. If there are
3:49more, uh, prey in the in the in an area,
3:53there will be more predators or they'll
3:55compete. Uh, accumulation of waste in an
3:58area can affect the number of organisms
4:01in there. The food, space, or shelter
4:04can also affect the size of the
4:06population. And parasites and diseases
4:09can affect the size of the population.
4:11So, let's say we are having a large
4:12population and some of the organisms are
4:15affected by a disease there. Now, the
4:16disease will pass to other organisms and
4:19they'll also die. Those are
4:21density-dependent
4:23uh
4:24factors.
4:25So, we also have density-independent
4:28factors. This factors does not rely on
4:31the size of the population. So, whether
4:34the population size is small or the
4:36population size is larger as it can be,
4:39this factors can affect
4:42the population. They are abnormal events
4:44in nature and occur randomly. They can
4:47just occur even
4:49uh regardless of the size of the
4:50population. So, examples of them are
4:52tsunamis. A tsunami can attack um a
4:55population whether it's small or large.
4:58We have landslides, volcanic eruptions,
5:01veld and also floods.
5:04So, those are examples of our
5:07uh density-dependent and independent
5:09factors. So, learners must know this.
5:11They they know them. They must make sure
5:13that they revise them.
5:15And then lastly on this slide, we are
5:17having uh population parameters
5:19affecting the size of the population.
5:21Here, we are having uh the mortality,
5:23which is our death rate. The death rate
5:26will decrease the size of the
5:27population. Natality, our birth rate.
5:30The birth rate will increase the size of
5:32the population. And then we have
5:34immigration. Immigration uh will
5:37increase the size of the population
5:39because organisms will be uh moving from
5:42uh one
5:43one area into that area. So, the the
5:46population size will increase. And
5:48emigration
5:49is that uh
5:51parameter which will decrease the size
5:53of the population because organisms will
5:55be moving out of an area. So, here is
5:57our
5:58uh NB there. They might be asked in our
6:03uh upcoming examination. So, please
6:05revise those. I know you know them, so
6:07please revise them.
6:12Okay, as we move on colleagues and
6:14learners then uh, we are now on our
6:17third slide.
6:19Uh, determining the population size. So,
6:22when determining the population size, we
6:24know that we are having direct
6:26techniques and indirect techniques. So,
6:29direct techniques will be counting
6:32uh, heads of those organisms. So, the
6:35first technique is census whereby uh,
6:39they'll be counting the number of humans
6:41directly in an area or a country. And
6:44the second technique is the aerial
6:47photography. Here, the the photo will be
6:50taken, the aerial photo will be taken,
6:52and the number of organisms on that
6:54photo will be counted. These are direct
6:56techniques. And then indirect techniques
7:00those are estimations. It means uh,
7:04uh, we are going to estimate the size of
7:05the population in in that area. So, the
7:08first one is mark and recapture method.
7:12And then the the the second one is the
7:14quadrats method. I know all of them were
7:17done in class and were done in the test,
7:20but we are just reminding you of them.
7:22So, the mark and recapture method as an
7:25example of an of an indirect technique
7:28is um,
7:29uh,
7:30is here on my slide. So,
7:33uh, the mark and recapture method uh,
7:35what what we are expected to do in the
7:37mark and recapture method as an example
7:39here they are saying it's especially
7:41suit- suitable for fish in a dam. So, we
7:44are going to have an example of fish in
7:46a dam. So, uh, we catch the number of
7:50individuals
7:52of fish uh,
7:54as we go with this example, we'll mark
7:57the fish and throw them back into the
7:59dam. So, after catching the first
8:01sample, we mark that fish and throw them
8:04back into the dam. And then we will
8:07allow them to disperse. We allow them to
8:10mix with other with other fish in the
8:12dam.
8:13It means we're going to give them enough
8:15time to mix with other organisms in the
8:18dam.
8:19And then
8:20after a while, let's say after a week,
8:22we'll make another second catch. So, the
8:24second catch will be our second capture
8:27and then count the number of marked
8:29individuals in that
8:32in that
8:34catch and then after that we are going
8:36to use this formula. So, this formula
8:38says P is the number of the the
8:42population size that we are calculating.
8:44M is the number of the first of the
8:47first catch. It means the number that
8:48you marked
8:50and then throw back in into the dam.
8:53And then we multiply by C. C here will
8:56be our second catch.
8:59The total number of organisms in the
9:00second catch. You count the ones you
9:02marked together with the ones which are
9:04not marked. That is the second catch.
9:07And then you divide by R. R here is the
9:10marked marked organisms in the second
9:12catch. So, here is a note here. Note
9:16that different letters can be used in
9:18this formula. But you have to know that
9:20it's
9:22the population size is equals to the
9:25number of fish
9:27in in the second catch multiplied by the
9:30the number of fish. Also, in the first
9:33one you multiply with the second catch
9:35and you divide by the marked fish in the
9:39second catch.
9:42And then
9:44here are examples of what I've just
9:47done.
9:48I have
9:49example of question this year. So,
9:52example of question number one says name
9:55two density dependent factors and
9:57density independent factors that can
9:59affect the population size. So, here are
10:01the answers. Predation, diseases,
10:04competition, food shortage,
10:07shelter shortage. Those are density
10:09dependent. And density independent
10:11factors drought, floods, as I
10:14have said from the previous slide.
10:16And then the second question, identify
10:19the growth form
10:20in the following in the following graph.
10:22So, the growth form is a logistic growth
10:25form.
10:26And then the same question says,
10:28identify the phases 1 to 4 in the above
10:31graph. So, phases 1 to 4 here are they
10:33here are the answers. As they were in in
10:36in the previous slide. The phase phase
10:38number one is the lag phase, number two
10:40exponential phase, number three the
10:43death phase, and lastly we have our
10:46equilibrium phase.
10:48And then number four, give one reason
10:50why the population growth is slower at
10:53phase number one. So, here is it should
10:56have been phase number one. So, at phase
10:59number one there's predation, lower
11:01reproductive rate, there are diseases,
11:03or there's competition here at phase
11:05number one. One of them might be a
11:07reason why there's a very slow growth
11:10there. And number five,
11:13name two population parameters that
11:14affect the population growth, natality,
11:17mortality, immigration, and emigration.
11:20Two of them, any two of them would be
11:21correct for this for this answer. I
11:23mean, for this question. Thank you.
11:26And as I move on, example of questions
11:29continued with the
11:31mark and recapture method. So, this is
11:34determining the population size. So, we
11:36said firstly we have to
11:39capture a number number of fish from the
11:42dam and then mark them.
11:44We mark them and after marking them we
11:47release them back into the sea into the
11:49the dam. So, here it means four fish
11:51were captured, marked with a red
11:55marking there and then released back
11:57into the dam. And then number two,
12:00you allow them time to mix you allow
12:03them time to mix with other fish and
12:05then you will come again and
12:08recapture. When you recapture you
12:10capture
12:12other
12:13fish.
12:15You means they will include those that
12:17you marked in the first capture. So,
12:19here we are having the total number of
12:21fish in the second capture is 16, and
12:24then those that are marked in the second
12:27catch is
12:29two. We have two fish which are marked.
12:32So,
12:33>> [snorts]
12:33>> when we continue, number six there says,
12:36"Use the information above to estimate
12:38the population of fish in the lake or in
12:40the dam." So, six
12:43when you calculate like you do in maths,
12:45you'll
12:47you'll have your formula there and
12:48identify the unknown and identify the
12:51variables that you have values for, then
12:53you'll be able to substitute in this in
12:55the formula and get the number. So, P is
12:57unknown. It's the estimated population.
13:00Four is the original number of fish
13:02captured, marked, and released.
13:05C is the total number of fish in the
13:09second capture. And R is the number of
13:12marked fish in the second capture. So,
13:15you substitute in the formula here,
13:18and we got 32 fish. So, the estimated
13:21number of fish in that lake or dam is
13:2532.
13:26So, that is how you calculate the the
13:28population size. And number seven says
13:31here from questions, "How can
13:33reliability be be ensured when using
13:35this method?"
13:37So, here is our
13:39here are our answers on how reliability
13:42can can be ensured when using the mark
13:44and recapture method. So, the first way
13:47in which the reliability can be ensured
13:50is that a large sample size must be
13:52captured. So, we must ensure that we
13:54capture a large sample size as possible
13:57so that
13:58our results can be reliable. The second
14:00answer is that we we must ensure that
14:03the markings last or remain for the
14:05period of the procedure.
14:07>> [snorts]
14:07>> You ensure that you mark with
14:10something or a paint or something that
14:12will last uh the period of
14:15the procedure or the experiment.
14:17Number three, markings must be suitable
14:20and must not harm or interfere with the
14:23behavior or movement of the organisms.
14:25So, it means if you mark or when you
14:28mark those organisms that you captured
14:30in the first capture, you must ensure
14:32that they the markings don't hurt them.
14:34The markings are not that heavy. You
14:37don't put heavy stuff. You don't put the
14:39stuff that will
14:41make them other organisms shy away from
14:44them, run away from them. So, they might
14:46they must be able to mix with other
14:48organisms and not harm their behavior.
14:51Number four,
14:53marked organisms must be given enough
14:55time to mix with other organisms. You
14:57must not throw fish now and then after 2
15:00hours go and recapture. No, you give
15:01them enough time so that they can mix
15:04and um
15:05do their
15:07daily routines in the dam they. And
15:10lastly, several samples must be taken
15:12and the average population
15:14size must be calculated. Like in any
15:16other experiment, uh the average must be
15:21uh taken after several samples uh
15:25calculated from that formula. So, these
15:29are our um
15:31ways in which reliability can be
15:33ensured. Maybe three or two ways can be
15:36asked, how can reliability be ensured in
15:40a mark and recapture method?
15:43Thank you. I hope we are still together,
15:45colleagues and learners.
15:47So, the the second slide is the
15:50following slide is our scientific
15:51investigation skill.
15:54So, we've been talking about the
15:55scientific investigation skills, I think
15:57from when
15:59question two was done last week. So,
16:02here I'm just having an example. I'm not
16:05going to go
16:06uh into that much detail of the
16:09scientific investigation skills. With
16:10this example, we'll be able to identify
16:14all the scientific investigation
16:15variables that are needed. So,
16:18the the experiment is taken from grade
16:2111 September paper and it was just
16:24modified a bit.
16:26Wearing a face a face mask is a
16:28recommended to reduce the spread of
16:30coronavirus.
16:32There are some concerns about the
16:34efficiency of breathing when wearing a
16:36face mask.
16:37So, when we move on it says, "Scientists
16:40investigated the effect of wearing face
16:42masks on the carbon dioxide levels." So,
16:46uh when
16:48every time when I do this the experiment
16:51with my learners or with any other uh
16:54learner,
16:56I say when we uh come across the aim,
16:59where it says, "Scientists investigated
17:01the effect of or the the effect of uh
17:05any other variable was investigated."
17:07So, here is our aim.
17:09And then from our aim, we have to
17:12underline or we have to make sure that
17:14we identify our dependent and
17:17independent variables even uh before we
17:20we are asked to identify them.
17:23Uh as long as when you come across the
17:25aim, you identify the variables. So,
17:27here it says, "Scientists investigated
17:29the effect of wearing a face mask masks
17:32on the carbon dioxide levels in the
17:34blood."
17:35So, carbon dioxide levels in the blood
17:37depends on wearing a face mask. So,
17:40we'll we'll know that our carbon dioxide
17:42level is our uh dependent variable. We
17:45write D here. And then wearing a face
17:47mask is our independent variable. We
17:50write I here. So, that when uh dependent
17:53and independent variables are asked,
17:55you'll be able to come and uh take them
17:59from the aim there. So, here is our
18:03independent and then here is our um
18:07dependent variable. And then when we
18:08move on, I say when we come to the
18:11procedure or the steps of the
18:12experiment, we have to identify um the
18:15variables that were kept constant. We
18:17identify the ways in which the
18:19reliability and validity, all those were
18:22ensured. So, we are going to read the
18:24first bullet there. It says
18:26uh
18:27the following steps were were taken.
18:29Obtained permission from 150 healthy
18:33male volunteers aged 30 to participate
18:36in the investigation. So, uh when they
18:39come across uh the number of
18:41individuals, 150,
18:43150, it means uh this is our
18:46reliability.
18:48Either uh the question will say how was
18:50reliability ensured or how could it it
18:53be ensured, but you write R
18:55R on top of 150. And then when when it
18:58says 150 healthy, it means all of them
19:01were healthy. So, they had they had uh
19:03the same
19:04health uh situation. They were they were
19:07all healthy. That This is also validity.
19:10And then all of them were males. The
19:12male is uh is the gender. All of them
19:14had the same gender. So, that is
19:17validity. You write V. And then they
19:19were aged eight. All of them had the
19:22same age. You write V. V stands for
19:25validity.
19:26And then we move on.
19:28The investigation was done in the same
19:30area. So, the area can be uh
19:33uh specific can be specific. They can
19:35say it was done in a a warm area, in a
19:38hot area, or the area where the carbon
19:41dioxide level is this much or
19:43atmospheric pressure and and so on. So,
19:45the same area is validity.
19:48The It means the experiment was done in
19:50the uh same area for all the volunteers.
19:53And then
19:55uh they applied a sensor to the
19:57participant's skin to measure the carbon
19:59dioxide levels in the blood. So, it
20:01means carbon dioxide was uh carbon
20:03dioxide levels was measured in the same
20:05uh procedure. So, they applied a sensor.
20:08This is validity. The same procedure or
20:10the same method was used to measure uh
20:13the carbon dioxide level. And then when
20:16we move on,
20:18uh the participants were asked to
20:21sit for 10 minutes without wearing a
20:23face mask and they see uh they also sit
20:26still for 10 minutes while wearing a
20:27face mask. So, they sit for the same
20:30duration without wearing a face mask,
20:32which is 10 minutes, and they also sit
20:35for 10 minutes with wearing a face mask.
20:37So, this is also valid. This is
20:41same duration of 10 minutes. Remember,
20:43we have to mention 10 minutes. Here, we
20:45also have to mention 150 volunteers, not
20:49just a large number of volunteers.
20:51So, they allowed 15 minutes intervals
20:54between the 10-minute phase.
20:57And then, they recorded the carbon
20:59dioxide levels at the end of each 10
21:01minutes. So, this 10 minutes It means
21:04they recorded the carbon dioxide levels
21:07after the same duration. They ensured
21:10that the face mask covered the nose and
21:12mouth. That was just a procedure. So,
21:15here are the results obtained.
21:17And then, at 0 minutes,
21:20with without a face mask, the carbon
21:23carbon dioxide level was seven. And
21:25also,
21:27it means
21:28the carbon dioxide level was seven.
21:31Um
21:32At the beginning of both the
21:33experiments,
21:35without a face mask and also when they
21:38wore a face mask. And then,
21:41after 10 minutes of where of
21:45them not wearing a face mask, the carbon
21:47dioxide levels
21:49now
21:50is the carbon dioxide level decreased.
21:52And then, when they were wearing a face
21:55mask, the carbon dioxide level
21:57increased.
21:58So, these are the results. So, when you
22:01have to interpret the results, you come
22:03here. And then, when you have to
22:04conclude, you also come here and look at
22:07the results and then go up and answer
22:10the aim using the information from the
22:13results. And then, questions from this
22:16experiment short experiment of ours.
22:18Number one, identify the dependent and
22:20independent variables. Independent,
22:22wearing a face mask. Dependent, carbon
22:24dioxide levels in the blood. So,
22:27I I know we are going to fight when
22:29marking this when discussing the the
22:31marking guideline. Some educators will
22:34fight to mark the carbon dioxide levels.
22:38This uh
22:39dependent variable must be written in
22:41full.
22:42It's carbon dioxide levels in the blood
22:44because there can be carbon dioxide
22:46levels in the atmosphere, carbon dioxide
22:47levels anywhere. So, this is carbon
22:50dioxide level in the blood. So, the mark
22:53is there. If learners
22:55learners who are listening now, please
22:57don't write just carbon dioxide levels.
22:59Write carbon dioxide levels in the
23:01blood. You'll get your one mark.
23:03Number two, state three factors that
23:06were kept constant when selecting
23:07participants. So, here you you go back
23:12as a learner, you go back to your
23:14experiment, you look where you wrote V.
23:17V stands for validity. It means those
23:19things were the same for all
23:20participants. All participants were
23:22healthy.
23:23Uh and then they were males.
23:25And they were 30 years old.
23:28When looking at only participants, not
23:30the area, not the time, and all those.
23:32Validity for those participants. And
23:36those factors that were kept constant
23:37were that they were healthy, they were
23:39all males, and they were 30 years old.
23:42So, you get your marks if you wrote like
23:44that. You don't say they had the same
23:46age.
23:48They had the same gender. No, no, no. We
23:50don't mention that.
23:51And number uh
23:53three, how was reliability ensured? So,
23:56if the question says how was reliability
23:59ensured, it means
24:01uh it talks about the past tense. What
24:03is already done. It means that you are
24:05just going to go to the
24:07procedure and take the answer. So, what
24:09was done is that 150 participants were
24:12were used in this experiment. But if the
24:14question said
24:16how could reliability be ensured? It
24:18means in future, what can they do to
24:21ensure that their experiment is
24:24uh reliable? It means here the answer
24:27could have been you you they could
24:29increase the number of participants to
24:32more than 150 or they they could use
24:35more than 150 participants.
24:38So, that that is how
24:40our reliability question is answered.
24:43Also,
24:45I forgot to include the time there. They
24:47can um
24:49record the carbon dioxide after after 10
24:53minutes or they can
24:55um
24:56record the carbon dioxide after more
24:58than 10 minutes.
25:00So, number four, why was carbon dioxide
25:03levels measured while participants were
25:05not wearing a mask? So, that is a
25:07control. Why? Why? Why? Because it's two
25:11marks, you have to go on and explain. To
25:13ensure that wearing a mask
25:16wearing a face mask is the only factor
25:18that affects carbon dioxide levels in
25:20the blood in this situation and that
25:23increases validity. So, we'll know that
25:25carbon dioxide level is the only factor
25:28that increases
25:29that affects Sorry, that wearing a face
25:32mask is the only factor that affects
25:34carbon dioxide levels in the blood and
25:37that results in an increase in validity.
25:39So, here
25:41in the question of a control, colleagues
25:43and learners, please let's shy away from
25:46writing that answer that what that we
25:48used to write
25:50uh 20 years back
25:52which says a control is used to compare
25:55results and and so on. So, we we we we
25:58say it is a control, we ensure that our
26:02independent variable is the only factor
26:04that affects our dependent variable in
26:07this experiment. So, you'll mention the
26:08independent variable is wearing a face
26:10mask and the dependent variable is the
26:13carbon dioxide levels in the blood.
26:15So, that is how we answer a control.
26:18Number five,
26:20draw up a conclusion for this
26:21experiment. So,
26:24uh our conclusion is we go here, we saw
26:26that uh when wearing a face mask, the
26:28carbon dioxide
26:30um
26:31level
26:32decreases.
26:33Uh increases increases in the blood. So,
26:36wearing a face mask decreases the levels
26:39of the carbon dioxide levels in the
26:41blood. From the uh our A in there it
26:44said uh scientist investigated the
26:47effect of wearing face masks on the
26:49carbon dioxide levels in the blood. So,
26:51we answer that A. Wearing a face mask
26:54decreases carbon dioxide
26:57Sorry, it must increase. I made a I made
26:59a mistake here. It must increase the
27:01carbon dioxide level in the in the
27:04blood. So, the answer is say the answer
27:06will be wearing a face mask increases
27:09carbon dioxide levels in the blood
27:11because it was seven, now it's 15. And
27:15um please note there'll be a graph drawn
27:18in our uh question paper. Please
27:20practice drawing how to draw graphs.
27:24When we move on,
27:26we move on to our genetically uh
27:29genetically modified crops uh or
27:31genetically modified organisms, but
27:34we'll be focusing on genetically
27:35modified crops
27:37and our alien plants. So,
27:40uh what are genetically modified crops?
27:42They are crops of which their DNA or
27:45genetic material is altered or changed
27:48to satisfy human needs. So, what are
27:51those human needs? They'll be high crop
27:53yield, improved nutritional quality,
27:56and increased food security and for
27:59others. So, these are our genetically
28:01modified uh crops. So, you have to uh
28:04read and answer uh about genetically
28:07modified crops. And then we have our
28:10alien plants. What are alien plants?
28:12They are unwanted crops.
28:14They compete with indigenous crops for
28:17water, nutrients, and sunlight. So, I
28:20got this picture there from AI. It says
28:24uh here it shows large uh trees there.
28:27It means these larger trees uh uh
28:30uh are able to absorb more water, more
28:32nutrients, and they also hide uh our uh
28:36our
28:37indigenous plants. They cannot receive
28:40enough sunlight. So, these are
28:42our
28:44alien plants, and these down there are
28:46our indigenous plants. So, how can alien
28:50plants
28:51invasion be controlled? How can we
28:54remove these plants when they invade our
28:57our areas. Number one, number one, we
29:00can remove them mechanically.
29:02Mechanically by hands or machines. We We
29:05remove them
29:06mechanically. Number two,
29:10they can be controlled chemically by the
29:12use of herbicides. We know that
29:13herbicides are those
29:15chemicals that kill unwanted plants. So,
29:19we can use those herbicides to kill the
29:21alien plants. And then lastly, we can we
29:24can use the biological method. The
29:26biological method is that
29:28method where the introduction of natural
29:31enemies in the habitat is done. So,
29:34let's say there are plants of which we
29:37know that if we can introduce rats that
29:40are not harmful to our indigenous
29:43plants, those rats can be able to eat
29:45those unwanted plants.
29:48So, this is what we
29:50we should know for the upcoming paper
29:53two in question three. Thank you very
29:56much. And then when we move on,
29:59we have poaching.
30:02Here on this slide, it just says what is
30:05poaching. It is illegal hunting or
30:07trapping of wildlife for food or profit.
30:11And we are having elephants and black
30:13rhinos, which are the most common
30:15animals which are poached. So, here are
30:18our elephants. They We poach them for
30:20for the elephant tusks. And then the the
30:23rhinos, we poach for the rhino horns so
30:27that we can make ornaments and sell
30:30them.
30:31So,
30:32I think this

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