Protein Control Of Cell Division

Question 1

What is a microtubule and what are they made of

Answer 1

Straight hollow cylinders composed of globular proteins called tubulins (A and B tubulin)

Question 2

Where do microtubules originate from

Answer 2

RADIATE from the microtubule organising centre (MTOC) which is located near the NUCLEUS

Question 3

What are three functions of the cytoskeleton

Answer 3

1. Gives mechanical support to the shape of the cell
2. Microtubules CONTROL MOVEMENT OF MEMBRANE BOUND ORGANELLES AND CHROMOSOMES
3. Microtubules play important roll in CELL DIVISION as the process requires remodelling of the cell’s cytoskeleton. Microtubules also form the SPINDLE FIBRES in cell division

Question 4

Name the two stages in the cell cycle

Answer 4

1. Interphase
2. Mitotic phase

Question 5

What are the three sub-phases of interphase

Answer 5

1.G1
2. S phase
3. G2

Question 6

Describe phase G1

Answer 6

Is a phase used for INITIAL GROWTH where proteins and organelles are SYNTHESISED

Question 7

Describe S phase

Answer 7

Continues to grow and DNA IS REPLICATED for mitosis

Question 8

Describe G2 phase

Answer 8

Further growth phase and organelle synthesis continues in preparation for mitosis

Question 9

What happens at the end of G2 phase

Answer 9

Cells enter the MITOTIC PHASE (M) phase

Question 10

What are the two stages of (M) phase

Answer 10

1. Mitosis
2. Cytokinesis

Question 11

What are the four stages of mitosis

Answer 11

1. Prophase
2. Metaphase
3. Anaphase
4. Telophase