The Cell Cycle + Cancer

Question 1

Name the three stages of the cell cycle

Answer 1

Interphase, nuclear division (nucleus divides into 2 or 4 - mitosis or meiosis) and cytokinesis (division of the cytoplasm to produce 2 or 4 new cells)

Question 2

One way to check for tumours + what causes the growth of tumours

Answer 2

• There are checkpoints between each stage of cycle, regulated by control genes
• Mutated control genes can cause cells to divide uncontrollably, leading to tumours

Question 3

Name three risk factors of cancer

Answer 3

Half of all cancers are preventable by change in lifestyle:

• Smoking
• Diet (high fat, low fibre, few fruit + veg)
• Obesity
• Physical activity
• Sunlight

Question 4

Name the two types of tumour and describe the difference between them

Answer 4

Benign - slow-growing, doesn’t spread to other parts of the body, not classed as cancer
Malignant - fast growing, often spread, classed as cancer

Question 5

Name three types of treatment for cancer

Answer 5

Surgery - removing tumour
Radiotherapy - radiation damages DNA of cells in tumour
Chemotherapy - medication

Question 6

Describe what chemotherapy does to stop cancer from worsening

Answer 6

• Blocking enzymes involved in DNA synthesis
• Preventing DNA unwinding
• Inhibiting synthesis of new nucleotides
• Prevent development of the spindle

Question 7

Give an example of drugs used for chemotherapy and what they do

Answer 7

• Adriamycin + cytoxan inhibit DNA helicase (enzyme that unwind DNA), so stops DNA replication
• Methotrexate inhibits nucleotide synthesis, so stops DNA replication