Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.
-
Upload
lambert-thomas -
Category
Documents
-
view
231 -
download
0
Transcript of Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.
![Page 1: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/1.jpg)
Cell Cycle RegulationChapter 9Section 3
![Page 2: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/2.jpg)
Main IdeaThe normal cell cycle is regulated by cyclin proteins
![Page 3: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/3.jpg)
Normal Cell CycleTo start the cell cycle in eukaryotic cells is driven by a combination of two substances that signal the cellular reproduction processes
Proteins called CYCLINS bind to enzymes called CYCLIN-DEPENDENT KINASES (CDKs)
![Page 4: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/4.jpg)
Different cyclins and CDK combinations control different activities at different stages in the cell cycle
![Page 5: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/5.jpg)
Quality control CheckpointsThe cell cycle also has built in checkpoints to
monitor the cycle and can stop it if something goes wrong
At the end of G1 stage a checkpoint monitors for DNA damage and can stop the cycle before entering the S stage of interphase
![Page 6: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/6.jpg)
Abnormal Cell Cycle: CANCERAlthough the cell cycle has a system of checkpoints, these checkpoints sometimes fail
When cells do not respond to the normal cell cycle control mechanisms, a condition called cancer can result
![Page 7: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/7.jpg)
CANCER is the UNCONTROLLED GROWTH and DIVISION OF CELLS
Cancer cells grow and divide unrestrained as long as they are supplied with essential nutrients
![Page 8: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/8.jpg)
![Page 9: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/9.jpg)
Causes of CancerCancer can occur in many healthy,
active and young organisms
The changes that occur in the regulation of cell growth and division of cancer cells are due to mutations or changes in the segments of DNA that control the production of proteins, including the Cyclins that control the cell cycle
![Page 10: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/10.jpg)
Carcinogens are substances and agents that are known to cause cancer
Examples of CarcinogensTobaccoSecond hand smokeAsbestosUltraviolet radiation (sunlight)X-rays
![Page 11: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/11.jpg)
Cancer GeneticsMore than one change in DNA is
required to change an abnormal cell into a cancer cell
Since multiple changes must occur this might explain why cancer runs in some families an individual who inherits one or more changes from a parent is at a higher risk of developing cancer than someone who does not
![Page 12: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/12.jpg)
ApoptosisNot every cell is destined to survive
APOPTOSIS is PROGRAMMED CELL DEATH
For example: when the human hand and foot are developing, the cells between the fingers and toes goes through apoptosis
![Page 13: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/13.jpg)
Stem CellsAre unspecialized cells that can develop into specialized cells when under the right conditions
There are two types of Stem cells: embryonic and adult
![Page 14: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/14.jpg)
Embryonic Stem CellAfter a sperm fertilizes an egg, the result is a mass of cell divides repeatedly until there are about 100-150 cells
If separated, each of these cells has the capability of developing into a wide variety of specialized cells
![Page 15: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/15.jpg)
Embryonic stem cell research is controversial because of ethical concerns about the source of the cells
![Page 16: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/16.jpg)
Adult Stem CellsAre found in various tissues in the
body and might be used to maintain and repair the same kind of tissue in which they are found
An example of use for adult stem cells: researchers used pancreatic stem cells to restore pancreas function in a mouse with diabetes
![Page 17: Chapter 9 Section 3. Main Idea The normal cell cycle is regulated by cyclin proteins.](https://reader036.fdocuments.net/reader036/viewer/2022062304/56649e545503460f94b4b9e3/html5/thumbnails/17.jpg)
Adult stem cells is much less controversial because the adult stem cells can be obtained with the consent of their donors