Cell Division

Question 1

How do prokaryotes replicate?

Answer 1

binary fission

Question 2

What are the 3 parts of binary fission?

Answer 2

a) DNA replication (B period)
b) replicated chromosomes move to ends of cell (C period)
c) membrane pinches and forms 2 daughter cells (D period)

Question 3

What are the 7 stages of mitosis?

Answer 3

1. Interphase
2. Prophase
3. Pro metaphase
4. Metaphase
5. Anaphase
6. Telophase
7. Cytokinesis

Question 4

What are the 3 parts of interphase?

Answer 4

G1 phase (cell growth and function)
S phase (DNA replication)
G2 phase (preparation for mitosis)

Question 5

What is G0 phase?

Answer 5

An additional phase of mitosis that cells may enter to act as an arrest

Question 6

What happens in prophase?

Answer 6

• chromosomes condense
• nucleolus shrinks
• mitotic spindle begins to form which forms the spindle poles

Question 7

What happens in pro metaphase?

Answer 7

• spindle microtubules grow from centrosomes
• spindles attach to chromosomes
• kinetochore forms on sister chromatids

Question 8

What happens in metaphase?

Answer 8

• spindles reach final form

- align chromosomes at midpoint

Question 9

What happens in anaphase?

Answer 9

• sister chromatids separate and move towards opposite poles

Question 10

What happens in telophase?

Answer 10

• spindle disassembles
• chromosomes decondense
• nucleolus reappears
• new nuclear envelope reappears

Question 11

What are the 2 forms of cytokinesis?

Answer 11

1. Furrowing

2. Cell plate formation

Question 12

What occurs in furrowing?

Answer 12

microtubules lay groundwork for microfilaments that form a plasma membrane deep enough to cleave the cell in two

Question 13

What occurs in cell plate formation?

Answer 13

same layer of microtubules lay the groundwork for vesicles that form a layer as the vesicles fuse together forming a plate

Question 14

What are the 2 ways through which chromosomes move?

Answer 14

1. motor proteins on kinetochore

2. motor proteins on microtubules

Question 15

Where are the 3 checkpoints in cell cycle regulation?

Answer 15

G1 phase/beginning of DNA synthesis
G2 phase/mitosis checkpoint
Mitotic spindle checkpoint

Question 16

What are 3 key characteristics about cancer cells?

Answer 16

• cells don’t understand regulatory signals to stop so they keep replicating
• loss of apoptosis causes more damage to already damaged cells
• cancer cells look very bizarre