CELL GROWTH DIVISION 10-1 10-2. Pre-assessment Quiz Cell Growth and Division.
Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate...
-
Upload
melissa-carson -
Category
Documents
-
view
247 -
download
1
Transcript of Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate...
![Page 1: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/1.jpg)
Chapter 8: Cell Growth and Division
![Page 2: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/2.jpg)
Cell Growth
Describe cell growthDefine cell divisionRelate cell growth to cell division
![Page 3: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/3.jpg)
Why do cells divide?
To reproduce To grow bigger To repair injuries To become more efficient
![Page 4: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/4.jpg)
Limits of Cell Growth1. Volume grows faster than surface area
2. Therefore a larger cell has a more difficult time getting stuff into (oxygen & nutrients) and out of (wastes) the cell
3. SOLUTION: Cell Division
![Page 5: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/5.jpg)
Rates of Cell Growth
1. Vary depending on cell type
2. E. Coli divide every 30 minutes
3. Some cells take much longer to divide or “stop” dividing for a while
![Page 6: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/6.jpg)
Controls on Cell Growth
1. Some cells rarely/never divide – nervous and heart cells
2. Some cells divide daily – skin and digestive tract cells
3. STOP switch: cells stop growing when they bump into each other
4. ON switch: cut or break in tissue cause cells to grow rapidly (but growth slows as healing reaches completion)
![Page 7: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/7.jpg)
Cell Division: Mitosis & CytokinesisDefine mitosis and cytokinesisDescribe the cell cycle and the
changes that take place during interphase
Discuss the events and significance of mitosis
![Page 8: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/8.jpg)
Chromosomes1. Chromosomes:
o “colored body”o seen only when the cell divideso contain genetic info in the form of
DNAo are coiled chromatin
2. Composition of Chromatino Make up chromosomeso Composed of DNA and protein
called histones (helps to condense the DNA)
o DNA in a chromosome is 10,000x longer than the chromosome itself
o Must condense in order to separate correctly during mitosis
![Page 9: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/9.jpg)
o Can only see chromosomes during division
o Each chromosome replicates and is paired as sister chromatids joined at a centromere
o Human cell = 46 chromosomes (2n)
“n” number = 23 = “haploid”
2n = 46 = “diploid” 4n = 92 (during interphase) Body cells (aka somatic
cells) = 2n = 46 Sex cells (aka eggs & sperm)
= n = 23
Chromosome Structure
![Page 10: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/10.jpg)
The Cell Cycle
1. Growth, prepares for division, divides (anywhere from 6 hours to 100 days)
2. 3 Partso Interphaseo Mitosis (PMAT) - few
minutes to several days
o Cytokinesis
![Page 11: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/11.jpg)
Interphase – 3 stages
More than 90% of the life of a cell is spent in this phase
G1: cell growth, development, and protein production (longest)
S: “Synthesis”, DNA replication
G2: Organelles replicated (shortest)
Note: DNA exists as chromatin (no chromosomes yet)
![Page 12: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/12.jpg)
Mitosis - Prophase
Longest phase of MITOSIS (50-60 % of total time required for mitosis)
Nuclear membrane starts to disintegrate
Chromosomes condense (become visible) – seen as 2 identical chromatids lying side by side held together by centromeres
Centrioles move to opposite poles
Spindle fibers grow from centrioles, attach at centromeres
![Page 13: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/13.jpg)
Mitosis – Metaphase (hint “m”=middle)
Chromosomes attach to the spindle fibers
Chromosomes line up in the middle (aka equator)
Spindle fibers run from centrosomes to centromeres of the chromosomes
![Page 14: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/14.jpg)
Mitosis - Anaphase (hint “a” = away)
Centromeres split Spindles retract and pull
sister chromatids apart Chromosomes move to
opposite poles (toward centrioles)
![Page 15: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/15.jpg)
Mitosis - Telophase
Chromosomes cluster at poles
Chromosomes uncoil – back into chromatin
Nuclear envelope reforms around each new nuclei
Mitosis is done Cell membrane begins to
pinch in the middle
![Page 16: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/16.jpg)
Cytokinesis Cell membrane moves inward and pinches in the middle
forming two identical cells In plant cells – a cell plate (eventually becomes the cell
wall) and cell membrane appear separating the 2 new cells
There are now 2 identical cells – same DNA, etc.
![Page 17: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/17.jpg)
http://media.pearsoncmg.com/bc/bc_campbell_concepts_5/media/assets/interactivemedia/activityshared/ActivityLoader.html?c6e&12&03&8B%20Mitosis%20and%20Cytokinesis%20Animation
http://media.pearsoncmg.com/bc/bc_campbell_concepts_5/media/assets/videos/AnimalMitosis-V.html
![Page 18: Chapter 8: Cell Growth and Division. Cell Growth Describe cell growth Define cell division Relate cell growth to cell division.](https://reader035.fdocuments.us/reader035/viewer/2022081418/56649e765503460f94b77a80/html5/thumbnails/18.jpg)
Pop Quiz????
1. What is the main goal of cell division?2. What are the 3 phases of interphase?3. What are the 4 phases of mitosis?4. A cell has 12 chromosomes. At the end
of cell division how many cells will there be?
5. A cell has 12 chromosomes. At the end of cell division how many chromosomes will be in each cell?