Chapter 10. Roots grow deep into the dirt and some surface cells are“scratched” away So…...
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Transcript of Chapter 10. Roots grow deep into the dirt and some surface cells are“scratched” away So…...
![Page 1: Chapter 10. Roots grow deep into the dirt and some surface cells are“scratched” away So… Root Tip Cells must divide rapidly = MITOSIS!](https://reader035.fdocuments.net/reader035/viewer/2022070401/56649f1d5503460f94c34d4e/html5/thumbnails/1.jpg)
Cell Differentiation and Cell Growth Regulators
Chapter 10
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Why did we use Onion Root Tip Cells?
![Page 3: Chapter 10. Roots grow deep into the dirt and some surface cells are“scratched” away So… Root Tip Cells must divide rapidly = MITOSIS!](https://reader035.fdocuments.net/reader035/viewer/2022070401/56649f1d5503460f94c34d4e/html5/thumbnails/3.jpg)
Why did we use Onion Root Tip Cells?
Roots grow deep into the dirt and some surface cells are“scratched” away
So… Root Tip Cells must divide rapidly = MITOSIS!
![Page 4: Chapter 10. Roots grow deep into the dirt and some surface cells are“scratched” away So… Root Tip Cells must divide rapidly = MITOSIS!](https://reader035.fdocuments.net/reader035/viewer/2022070401/56649f1d5503460f94c34d4e/html5/thumbnails/4.jpg)
Why do cells divide?
Cell division allows organisms to grow and reproduce.
Also, cells cannot function effectively if they are too large. Compare the surface area to volume ratio.
![Page 5: Chapter 10. Roots grow deep into the dirt and some surface cells are“scratched” away So… Root Tip Cells must divide rapidly = MITOSIS!](https://reader035.fdocuments.net/reader035/viewer/2022070401/56649f1d5503460f94c34d4e/html5/thumbnails/5.jpg)
Why do cells divide?
![Page 6: Chapter 10. Roots grow deep into the dirt and some surface cells are“scratched” away So… Root Tip Cells must divide rapidly = MITOSIS!](https://reader035.fdocuments.net/reader035/viewer/2022070401/56649f1d5503460f94c34d4e/html5/thumbnails/6.jpg)
Cell Differentiation
Cell differentiation: when cells take on specific structures and functions Different organisms may have different
types of cells (e.g. bacterium) There may be many different types of
cells in the SAME organism (e.g. human)
![Page 7: Chapter 10. Roots grow deep into the dirt and some surface cells are“scratched” away So… Root Tip Cells must divide rapidly = MITOSIS!](https://reader035.fdocuments.net/reader035/viewer/2022070401/56649f1d5503460f94c34d4e/html5/thumbnails/7.jpg)
Examples of Slow Dividing Cells Neurons (top)
Conduct impulses throughout our body so that we can move, think, feel, etc
Some NEVER divide
Muscle cells (bottom) Used for movement Works like a spring
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Examples of Fast Dividing Cells
Cheek cells (top) Divide approximately
every three days because food scrapes off surface layers
Intestinal cells (bottom) Divides quickly because
food and bile scrape off surface layers
Frequently have cilia (hair-like projections) to help “move” food down the digestive tract
![Page 9: Chapter 10. Roots grow deep into the dirt and some surface cells are“scratched” away So… Root Tip Cells must divide rapidly = MITOSIS!](https://reader035.fdocuments.net/reader035/viewer/2022070401/56649f1d5503460f94c34d4e/html5/thumbnails/9.jpg)
How is cell growth regulated? Proteins called cyclins control parts of the
cell cycle.
Internal regulators are cyclins that control events INSIDE the cell. For example, some cyclins pause mitosis until
chromosomes are copied. Once this occurs, then it resumes mitosis.
External regulators are cyclins that control events OUTSIDE of the cell. For example, cells grow until they reach other
cells (e.g. healing a wound). Some cyclins tell the cells to stop dividing so that it won’t interfere with other tissues.
![Page 10: Chapter 10. Roots grow deep into the dirt and some surface cells are“scratched” away So… Root Tip Cells must divide rapidly = MITOSIS!](https://reader035.fdocuments.net/reader035/viewer/2022070401/56649f1d5503460f94c34d4e/html5/thumbnails/10.jpg)
What is cancer?
Cancer is uncontrolled cell division.
Since cancerous cells belong to the organism itself, the organism’s body has difficulty detecting and fighting the cancerous cells. Glycoproteins on cell
membrane are “self markers”
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What is cancer?
Cancerous cells tend to form a clump called a tumor, but sometimes in later stages of cancer, the cancerous cells metastasize. Metastasize means that
they move to other parts of the body. For example, a cancerous lung cell might migrate to the brain and spread the cancer.
![Page 12: Chapter 10. Roots grow deep into the dirt and some surface cells are“scratched” away So… Root Tip Cells must divide rapidly = MITOSIS!](https://reader035.fdocuments.net/reader035/viewer/2022070401/56649f1d5503460f94c34d4e/html5/thumbnails/12.jpg)
Causes
Inherited Genetic Mutation Carcinogens (e.g. certain
chemicals in cigarettes) Overexposure to
radiation (e.g. sunlight) Diet / Exercise Other
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Treatments
Surgery
Radiation
Chemotherapy
Magnets???
Alternative Options