6.1 The Cell Cycle

Question 1

What are teh two main phases of teh cell cycle

Answer 1

Interphase

Mitotic phase

Question 2

What the main idea of interphase

Answer 2

Here are long periods of growth

Cell spends majority of time here

Question 3

Key things that happen during interphase

Answer 3

DNA is replicated and checked for errors 
Protein synthesis occurs 
Mitochondria grow and dive 
Chrloroplasts grow and divide 
Normal metabolic processes of cell occur

Question 4

What are the 3 stages of interphase

Answer 4

G1 - cell grows
Proteins are produced and organelles replicate
S - synthesis phase and dna is replicated in nucleus
G2 - cell continues to grow
Energy stores increase
Duplicated dna is checked for errors

Question 5

What does the period of cell division (mitotic phase) involve in teh cell cycle

Answer 5

Mitosis - splitting of Nucleus

Cytokinesis - splitting of cytoplasm

Question 6

What is G0

Answer 6

Phase where cell leaves the cycle

Question 7

Why does G0 happen

Answer 7

Differentiation - cell becomes specialised and no longer divides
Dna of cell is damaged and so cannot divide and enters a period of cell arrest
The cells become SENESCENT

Question 8

What are checkpoints in teh cell cycle

Answer 8

Control mechanisms
Monitor and verify wether the processes of each phase of teh cell cycle have been accurately completed before the cell progresses

Question 9

Where is the G1 and G2 checkpoint

Answer 9

At the end of G1 phase - check cell damage and growth factors
End of G2 phase - check if dna is replicated without error
If not satisfied it will enter G0 phase

Question 10

What is the last checkpoint called and what’s it’s job

Answer 10

Spindle assembly checkpoint
In metaphase of mitosis
They check if all chromosomes are attached to spindle and have aligned