the cell cycle chapter 10, section 2. why do cells divide? §for growth, repair, and reproduction
TRANSCRIPT
![Page 1: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/1.jpg)
The Cell Cycle
Chapter 10, Section 2
![Page 2: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/2.jpg)
Why do cells divide?
For growth, repair, and reproduction
![Page 3: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/3.jpg)
When do cells divide?
Most limiting factor in size is the size of the cell membrane.
A cell has to stay small so that all the things that need to go in and out don’t have too far to travel. The surface area to volume ratio must be small so cells stay tiny and divide instead of growing too big.
![Page 4: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/4.jpg)
How Do Cells Divide?Cell cycle - sequence of phases
in the life cycle of the cell
![Page 5: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/5.jpg)
![Page 6: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/6.jpg)
![Page 7: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/7.jpg)
Interphase3 parts: G1, S and G2
G1 - cell growth; make new organellesS – DNA replicationG2 – short; organelles for cell
division are produced
![Page 8: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/8.jpg)
![Page 9: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/9.jpg)
What is Mitosis?The process whereby body
cells(somatic) are made by cell division
![Page 10: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/10.jpg)
How does it work?
4 Stages
![Page 11: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/11.jpg)
1st - Prophase
Chromosomes become visibleCentrioles go to opposite sidesSpindle fibers formNuclear membrane breaks down
![Page 12: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/12.jpg)
-2- Metaphase- Chromosomes line up along the equator in pairs-3- Anaphase- Chromosomes
move to opposite ends of the cell-4- Telophase- a cleavage
furrow forms and…each cell now has exactly the
same number of chromosomes!
![Page 13: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/13.jpg)
Cytokinesis
Cytoplasm pinches in half
![Page 14: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/14.jpg)
Mitosis
Results in an exact duplicate of the same cell. There is no change.
![Page 15: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/15.jpg)
![Page 16: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/16.jpg)
Interphase
![Page 17: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/17.jpg)
Prophase
![Page 18: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/18.jpg)
Metaphase
![Page 19: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/19.jpg)
Anaphase
![Page 20: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/20.jpg)
Telophase
![Page 21: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/21.jpg)
![Page 22: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/22.jpg)
![Page 23: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/23.jpg)
![Page 24: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/24.jpg)
MEIOSISChapter 11
![Page 25: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/25.jpg)
So, What is Meiosis?
The process whereby gametes or, sex cells are made by cell divisionExamples are sperm & eggs
only!
![Page 26: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/26.jpg)
How does it work? 8 Stages Prophase I
(includes chromosomes crossing over and exchange)
Metaphase IAnaphase ITelophase I
Prophase IIMetaphase IIAnaphase IITelophase II
![Page 27: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/27.jpg)
The same things occur with chromosomes except the number of chromosomes is halved
![Page 28: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/28.jpg)
Meiosis results in cells that have only 23 chromosomes in humansMen make 4 sperm cellsWomen make 1 egg and 3
polar bodies (which are excreted as waste products
![Page 29: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/29.jpg)
Why is meiosis so important?
It provides for genetic variation crossing over occurs in
prophase I and IIshuffling of chromosomes
(or genetic information)
![Page 30: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/30.jpg)
![Page 31: The Cell Cycle Chapter 10, Section 2. Why do cells divide? §For growth, repair, and reproduction](https://reader035.vdocuments.net/reader035/viewer/2022070411/56649f575503460f94c7c7d2/html5/thumbnails/31.jpg)
Mitosis MeiosisBody cells/
somatic cells4 Stages 1 divisionResults in 2
daughter cellsAsexual Growth2n - diploid
Sex cells / gametes8 stages 2 divisionsResults in 4 sperm or 1
egg & 3 polar bodiesSexual reproductionCrossing over – prophase I
1n - haploid