Cell Cycle

Question 1

What are the two key roles of the cell cycle

Answer 1

DNA replication and DNA segregation

Question 2

What are the 4 stages of the eukaryotic cell cycle

Answer 2

G1 - growth and prep for DNA synthesis
S - DNA replication
G2 - preparation for mitosis (replication)
M - mitosis and cytokinesis

Question 3

What defines mitotic stages

Answer 3

Chromosome behaviour

Question 4

What are the stages of mitosis

Answer 4

Prophase
Prometaphase
Metaphase
Anaphase
Telophase

Question 5

What happens during prophase

Answer 5

Chromatid pairs disentangle and condense in nucleus
nuclear envelope remains intact
Centrosomes are duplicated and begin to move to opposing poles

Question 6

What happens during prometaphase

Answer 6

Centrosome reaches the spindle pole
Breakdown of nuclear envelope
Chromosomes attach to spindle microtubules via kinetochore

Question 7

What is the kinetochore

Answer 7

Protein structure on chromatids where spindle microtubules attach during cell division

Question 8

What happens during metaphase

Answer 8

Centrosomes attach to spindle poles
Chromosomes are aligned at spindle equator

Question 9

What happens during anaphase

Answer 9

Sister chromatids synchronously separate
Daughter chromosomes move to spindle poles
Spindle poles move outwards

Question 10

What happens during telophase

Answer 10

Two sets of daughter chromosomes arrive at spindle poles
Chromosomes decondense
New nuclear envelope assembles
Contractile ring starts to contract

Question 11

What is the role of the contractile ring

Answer 11

Responsible for cytokinesis by squeezing the cell in two
Creates a cleavage furrow