Lecture One: Apoptosis and Necrosis

Question 1

What is apoptosis?

Answer 1

-programmed cell death
- the cell can make its own enzymes which can destroy the cell.
- membrane of cell would stay intact.
- no inflammation in apoptosis
- once the cell has been destroyed by apoptosis it will be consumed by phagocytes.

Question 2

Does apoptosis require ATP?

Answer 2

apoptosis is an active process and therefore it will require ATP where as necrosis does not.

Question 3

Give an example of a process which requires both apoptosis and necrosis?

Answer 3

MYOCARDIAL ISCHEMIA:
- the initial response will be apoptosis (avoids inflammation)
- the subsequent response will be necrosis (ATP depleted)

Question 4

What are the causes of apoptosis?

Answer 4

1. EMBRYOGENESIS
2. HORMONE WITHDRAWAL:
   occurs in hormone dependent tissues
   endometrium with progesterone has been withdrawn
3. IMMUNE CELLS: t cells in thymus, b cells in germinal centers, death of self reactive immune cells and immune cells after inflammation resolves.
4. DNA damaged cells
5. ABNORMAL CELLS
6. INFECTED CELLS

Question 5

What is the apoptotic mechanism causes by?

Answer 5

Apoptotic mechanisms are caused by caspase enzymes.
- these caspases are found in the cytosol in their inactive form
-the activated capases is whats causes apoptosis