Cell Injury

Question 1

What are the normal processes which maintain the steady cellular state?

-Cell injury occurs when these processes are interupted

Answer 1

1) Preservation of genetic integrity
2) Normal enzyme content
3) intact membranes and transmembrane proteins
4) Adequate supply of substrates and oxygen

Question 2

what happens when a normal cell undergoes stress?

Answer 2

• Adaptation

- If the cell is unable to adapt to stress then injury occurs

Question 3

What happens with when a cell undergoes irreversible injury?

Answer 3

CELL DEATH:

1) Necrosis
2) Apoptosis

Question 4

How does a cell adapt?

Answer 4

1) increased cellular activity :
- Hyperplasia
- Hypertrophy

2) Change in cell morphology
- Metaplasia

3) Decreased cellular activity
- Atrophy

Question 5

What is the cause of cell injury?

Answer 5

1) Oxygen availability
2) Trauma
3) chemical agents
4) infectious organisms
5) irradiation
6) Genetic
7) ageing
8) lack of nutrients

Question 6

What happens in the reduction of oxygen?

Answer 6

1) Hypoxia and anoxia

reduction of oxygen often caused by ischaemia

Question 7

What are the effects of Physical trauma to a cell?

Answer 7

1) mechanical trauma
- disrupts cell structure
- causes thrombosis&raquo_space;>Ischaemia

2) Extrenes of temperature
- Heat denaaturation of proteins
- Ice crystals

Question 8

What are chemical agents can cause cell injury?

Answer 8

• alcohol

- tobacco smoke

Question 9

How do infectious organisms causes cell injury?

Answer 9

1) Bacterial Toxin
- endo/exotoxins

2) Hijacking of cell by virus leading to cell lysis
3) damage from inflammation

Question 10

How does irradiation cause cell ingury?

Answer 10

-generation of free radicals damages cell molecules

Question 11

how to free radicals cause cell injury?

Answer 11

• free radicals are highly reactive molecules.
• It interacts with the membrane to produce more free radicals
• damages proteins and nucleic acids&raquo_space;>apoptosis

Question 12

What is necrosis?

Answer 12

• Necrosis is cell death that occurs as a result of lethal cell injury.
• causes inflammatory reaction
• passive process

Question 13

What are the morphological types of necrosis?

Answer 13

• coagulative
• caseous (TB)
• Colliquative (brain)
• Gangrene (wet and dry)
• Fat/fibrinoid

Question 14

What is coagulative necrosis?

Answer 14

• dead tissue become firm and swollen.

Question 15

What is colliquative necrosis?

Answer 15

Necrotic neural tissue can become liquified. The site is marked by a cyst

Question 16

What is caseous necrosis?

Answer 16

• occurs in TB
• cheese like as cell detail destroyed
• surrounded by granulomatous inflammation
• lacks structure

Question 17

What is apoptosis?

Answer 17

Apoptosis is programmed cell death.

-it is an active process and requires energy