Cell Division Mitosis and Meiosis. The Cell Cycle Mitosis Interphase.
Cell Cycle and Mitosis
description
Transcript of Cell Cycle and Mitosis
![Page 1: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/1.jpg)
Cell Cycle and Mitosis
9.1 Cell Cycle
![Page 2: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/2.jpg)
What is the cell cycle? Repeating series of events Five stages Interphase (3 parts)
G1
S G2
M phase (2 parts) Mitosis Cytokinesis
![Page 3: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/3.jpg)
What happens in Interphase? G1
Normal growth Recovery from last
mitotic division S
Replication of chromatids
G2
Synthesis of proteins for mitosis
![Page 4: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/4.jpg)
Cell Cycle and Mitosis
9.2 M phase: Mitosis and cytokinesis
![Page 5: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/5.jpg)
What happens during the M phase? Mitosis
Prokaryotes undergo binary fission instead
Cytokinesis
![Page 6: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/6.jpg)
What is a chromosome? Length of DNA with
genes and noncoding regions
Highly condensed version of chromatin Heterochromatin vs.
euchromatin
![Page 7: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/7.jpg)
What is mitosis? Division of nuclear
material Duplicated chromosomes
are split This creates unduplicated
chromosomes Chromosome terminology
Sister chromatids Kinetechore Centromere Diploid (2n) vs. haploid (1n)
![Page 8: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/8.jpg)
What are the stages of mitosis? Prophase Prometphase Metaphase Anaphase Telophase
![Page 9: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/9.jpg)
What happens in prophase? Nuclear envelope
disappears Centrioles move apart Nucleous disappears Chromatin condenses to
form chromosomes Recall that these are
duplicated
![Page 10: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/10.jpg)
What happens during prometaphase? Kinetechores appear Spindles attach Polar spindle fibers extend and overlap
![Page 11: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/11.jpg)
What happens during metaphase? Duplicated chromosomes align along
metaphase plate
![Page 12: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/12.jpg)
What happens during anaphase? Sister chromatids pulled apart Chromosomes are now
unduplicated
![Page 13: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/13.jpg)
What happens during telophase? Reverse of prophase Cleavage furrow develops in animal
cells
![Page 14: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/14.jpg)
What is the second part of the M phase? Cytokinesis
Cytoplasmic division Animal cells
Contractile ring Plant cells
Cell plate
![Page 15: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/15.jpg)
Cell Cycle and Mitosis
9.3 Cell cycle control and cancer
![Page 16: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/16.jpg)
Why do cells undergo mitosis? Repair and replacement
Apoptosis of somatic cells blebbing
Stem cells Serve as reservoir for replacing old cells
![Page 17: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/17.jpg)
What controls the cell cycle? Checkpoints
G1
Apoptosis if DNA is damaged
G2
M
![Page 18: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/18.jpg)
What is cancer? Uncontrolled cell growth Characteristics
Neoplasms (tumors) Benign vs. malignant Angiogenesis Metastasis Abnormal nuclei Undifferentiated (anaplasia) Lack contact inhibition No apoptosis
![Page 19: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/19.jpg)
How does cancer occur? Mutations of cell
repair genes Activation of
telomerase Mutations of
either/both Proto-oncogenes
Become oncogenes Tumor suppressor
cells
![Page 20: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/20.jpg)
What are proto-oncogenes? “gas pedal” of cell
division Mutated oncogene Examples
ras genes rasN (leukemia) BRCA1
![Page 21: Cell Cycle and Mitosis](https://reader036.fdocuments.us/reader036/viewer/2022062322/5681448f550346895db12857/html5/thumbnails/21.jpg)
What are tumor suppressor genes? Brake pedal of cell
division If mutated loss of
cell cycle control Examples
p53 gene RB gene