Mastering Biology BioFlix Animation Tour of an Animal Cell — Transcript

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1. 0:03even if you're just studying a lot of
2. 0:06work is going on in your cells
3. 0:08let's Zoom down
4. 0:10and check it out
5. 0:15we've arrived in the space between two
6. 0:17cells a sticky coat called The
7. 0:20extracellular Matrix holds the cells
8. 0:22together each cell is surrounded by a
9. 0:25flexible plasma membrane with an
10. 0:28incredible number of projections docking
11. 0:31stations and channels let's dive into
12. 0:33one of these channels to enter a cell
13. 0:39whoa look at this place
14. 0:41these girders and cables make up the
15. 0:44cytoskeleton the structural framework of
16. 0:47the cell
17. 0:48they also serve as tracks for
18. 0:50transporting cargo from one place to
19. 0:53another
20. 0:56all this activity in the cell requires
21. 0:59energy in the form of ATP molecules
22. 1:02which are made here in the mitochondrion
23. 1:04notice the outer membrane and the inner
24. 1:08membrane with its numerous infoldings
25. 1:11many of the molecules involved in making
26. 1:14ATP are built into the inner membrane
27. 1:17all those folds increase the inner
28. 1:20surface area enabling more ATP to be
29. 1:23made
30. 1:27moving towards the nucleus we pass by
31. 1:30layers of internal membranes the nucleus
32. 1:33is enclosed by a double membrane called
33. 1:36the nuclear envelope let's enter the
34. 1:39nucleus through a pore
35. 1:41the nucleus houses the genetic material
36. 1:43of the cell DNA which carries the
37. 1:46blueprints for making the cells proteins
38. 1:49almost two meters of DNA is crammed
39. 1:53inside the nucleus
40. 1:54how does it all fit
41. 1:56the DNA is wrapped around proteins like
42. 2:00thread wrapped around spools look this
43. 2:04section of the DNA has Unwound and a
44. 2:07different protein has attached to the
45. 2:09DNA DNA is being used as a template to
46. 2:13make mRNA mRNA molecules travel from the
47. 2:17nucleus to the cytoplasm carrying the
48. 2:21instructions for making specific
49. 2:22proteins
50. 2:23in the cytoplasm a ribosome clamps onto
51. 2:27a strand of mRNA the ribosome ratchets
52. 2:31along the MRNA building a new protein
53. 2:34some proteins stay in the cytoplasm
54. 2:37others like this one are processed in
55. 2:40special compartments within the cell
56. 2:46protein processing and certain other
57. 2:48metabolic activities occur in the
58. 2:51endomembrane system the cell's network
59. 2:54of internal membranes the endoplasmic
60. 2:58reticulum or ER is part of the
61. 3:01endomembrane system
62. 3:03there are two types of er rough and
63. 3:07smooth
64. 3:08rough ER is covered with ribosomes
65. 3:11smooth ER lacks ribosomes lipids are
66. 3:15made in the smooth ER
67. 3:17let's go inside the rough ER
68. 3:20note that you can still see the ribosome
69. 3:23on the outside surface
70. 3:25the ribosome is manufacturing a new
71. 3:27protein which continues to grow inside
72. 3:30the ER completed proteins move to the
73. 3:34edge of the rough ER and depart in a
74. 3:36vesicle that buds off from the ER
75. 3:39membrane some vesicles fuse with the
76. 3:42Golgi apparatus another component of the
77. 3:45endomembrane system
78. 3:47in the Golgi proteins undergo further
79. 3:51processing
80. 3:53finished proteins are then packaged in
81. 3:55vesicles that pinch off from the Golgi
82. 3:58and are transported along cytoskeleton
83. 4:00tracks
84. 4:01some vesicles bind with the plasma
85. 4:04membrane secreting their contents
86. 4:06outside the cell other vesicles called
87. 4:10lysosomes contain digestive enzymes here
88. 4:13a lysosome fuses with a worn out
89. 4:16mitochondrion and breaks it down each of
90. 4:20the trillions of cells in your body is a
91. 4:22Dynamo of activity requiring millions of
92. 4:25atps every minute
93. 4:28but most people are unaware of all this
94. 4:31activity in their cells