Apoptosis & Necrosis

Question 1

Define apoptosis.

Answer 1

Programmed cell death. Removal of a cell without release of harmful products.

Question 2

What does mitosis and apoptosis ensure?

Answer 2

Constant renewal of cells.

Question 3

List 3 characteristics of apoptosis.

Answer 3

1) energy dependant
2) enzymatic digestion
3) phagocytosis

Question 4

List 4 diseases due to defective apoptosis.

Answer 4

1) cancers
2) AIDS - HIV proteins activate CD4 which induces apoptosis of helper T lymphocytes
3) neurodegenerative disorders
4) anaemia of chronic disorders

Question 5

Define necrosis.

Answer 5

Traumatic cell death. Induces inflammation and repair.

Question 6

List 2 characteristics of necrosis.

Answer 6

1) failure to produce ATP

2) plasma membrane ruptures

Question 7

Why is inflammation and repair induced by necrosis? (5)

Answer 7

1) plasma membrane ruptures
2) cell contents spill out
3) some cell contents are immunostimulatory
4) stimulates inflammatory response
5) stimulates repair

Question 8

List 4 types of necrosis.

Answer 8

1) coagulative necrosis
2) liquifactive necrosis
3) caseous necrosis
4) gangrene