The Cell Cycle

Question 1

What are the three stages of the cell cycle?

Answer 1

Interphase, nuclear division and cytokinesis.

Question 2

What stage of the cell cycle dies no division take place?

Answer 2

Interphase.

Question 3

What stage occupies most of the cell cycle?

Answer 3

Interphase.

Question 4

What is nuclear division?

Answer 4

When the nucleus divides into two (mitosis) or four (meiosis).

Question 5

What stage does cytokinesis follow?

Answer 5

Nuclear division.

Question 6

What is cytokinesis?

Answer 6

When the cytoplasm divides to produce two (mitosis) or four (meiosis) new cells.

Question 7

What is cancer?

Answer 7

A group of around 200 diseases caused by a growth disorder of cells.

Question 8

What is cancer a result of?

Answer 8

Damage to the genes that regulate mitosis and the cell cycle.

Question 9

What does damage to the genes that regulate mitosis lead to?

Answer 9

Uncontrolled growth and division of cells.

Question 10

What develops and expands in size as a consequence of uncontrollable growth and division of cells?

Answer 10

A group of abnormal cells called a tumour.

Question 11

Where can tumours develope?

Answer 11

In any organ of the body.

Question 12

Where are tumours most commonly found?

Answer 12

The lungs, prostate gland, breast and ovaries, large intestine, stomach, oesophagus, and pancreas.

Question 13

When does a tumour become cancerous?

Answer 13

If it changes from benign to malignant.

Question 14

Why do cells divide by mitosis?

Answer 14

For growth or repair.

Question 15

What is mitosis controlled by?

Answer 15

Two types of gene.

Question 16

What does a mutation to one of the genes that control mitosis result in?

Answer 16

Uncontrolled mitosis.

Question 17

What are mutated cells capable of forming?

Answer 17

Clones of themselves forming tumours.

Question 18

What is the difference between malignant and benign tumours?

Answer 18

Malignant tumours grow rapidly, are less compact, and are more likely to be life-threatening, while benign ones grow more slowly, are more compact, and are less likely to be life-threatening.

Question 19

What does the treatment of cancer involve?

Answer 19

Killing dividing cells by blocking a part of the cell cycle, and hence disrupting cancer growth.

Question 20

How does chemotherapy disrupt the cell cycle?

Answer 20

Prevents DNA from replicating, and inhibits the metaphase stage of mitosis by interfering with spindle formation.

Question 21

What is a problem with chemotherapy?

Answer 21

It also disrupts the cell cycle of normal cells.

Question 22

What is chemotherapy most effective against?

Answer 22

Rapidly dividing cells.

Question 23

Why does chemotherapy damage cancer cells to a higher degree than normal cells?

Answer 23

They have a faster rate of division.

Question 24

Why is hair lost during chemotherapy?

Answer 24

As hair-producing cells have a high rate of division which is what chemotherapy is most effective against.