Ch 11. Cell cycle, mitosis, and Ch 12. meiosis (exam 4)

Question 1

List the phases of the cell cycle and briefly explain what happens in each of the phases.

Answer 1

G1: Growth

S: DNA synthesis

G2: Growth and preparation for mitosis

M: Mitosis (cell division)

Question 2

In which phase of the cell cycle does DNA replicate?

Answer 2

S Phase

Question 3

What happens when cell cycle check points do not work?

Answer 3

Cancer = uncontrolled cell growth

Question 4

What are the 6 phases of mitosis? Explain what is happening with regards to the chromosomes in each stage of mitosis. (Make sure you can use the terms “homologous chromosomes” and “sister chromatids” correctly.)

Answer 4

PPMATC

1. Prophase
2. Prometaphase
3. Metaphase
4. Anaphase
5. Telophase
6. Cytokinesis

Question 5

What is the difference between benign and malignant/metastatic tumors?

Answer 5

○Benign

• Abnormal cells do not spread
• Can be removed
• Typically does not cause problems

○Malignant/metastatic

• Abnormal cells travel to other locations in the body
• New tumors develop in these locations
• More serious

Question 6

What are the subphases of Meiosis I and Meiosis II? Explain what is happening with regards to the chromosomes in each stage of meiosis. (Make sure you can use the terms “homologous chromosomes” and “sister chromatids” correctly.)

Answer 6

Meiosis I
PPMAT+C
- Prophase I
- Prometaphase I
- Metaphase I
- Anaphase I
- Telophase I 
- Cytokinesis 

Meiosis II
PPMAT + C
- Prophase II
- Prometaphase II
- Metaphase II
- Anaphase II
- Telophase II 
- Cytokinesis

Question 7

Compare and contrast mitosis and meiosis.

Answer 7

Mitosis

• Eukaryotic cell goes through it
• Produce 4 gamete cells
• Parent cell is diploid
• Daughter cells are diploid
• 2 identical daughter cells (identical to parent cells too)
• DNA replicates once
• Cell division happens once

Meiosis

• Happens in germ cells
• Cell produce is ex cells or gametes
• Parent cell are diploid
• Daughter cells are haploid
• Daughter cells made are 4
• Daughter cells are not genetically identical to each other
• DNA replicates once
• Cell division occurs 2x

Question 8

Explain how “genetic recombination (crossing over)” and “independent assortment” increase genetic diversity during meiosis.

Answer 8

-Crossing over during prophase and independent assortment during anaphase produce sets of chromosomes containing new allele combinations, thus causing genetic variation.
(each daughter cell at the end of meiosis will contain a different combination of genetics from your mother & father)