A4 Case Study: Cell Injury

Question 1

What is the difference between anoxia and hypoxia?

Answer 1

Anoxia: No oxygen (o2)
Hypoxia: Low oxygen (o2)

Question 2

What are some possible causes of anoxia?

Answer 2

• Thrombus: Formation of blood clot, no blood flowing through.
• Ischemia: restriction of blood, hypoxia and anoxia can lead to cell swelling (hydropic swelling)

Question 3

What does a hypoxic cell look like?

Answer 3

Swelling, closely tight together

Question 4

What are some possible causes of hypoxia?

Answer 4

• Asthma: Inadequate transfer of oxygen across lung surfaces
• Anaemia: inadequate transport of oxygen in blood

Question 5

What are the different types of cell adaptations?

Answer 5

Atrophy, Hypotrophy, Hyperplasia and Metaplasia

Question 6

How are these cell adaptation different to one another?

Answer 6

Atrophy - Decrease size of tissue, organ or cell
Hypertrophy - Increase cell size and increased cell capacity
Hyperplasia - Cells undergo mitotic divisions increasing number of cells
Metaplasia - Abnormal replacement of one (differentiated) cell type by another (Adaptive substitution of cells)

Question 7

What is Apoptosis?

Answer 7

The process of programmed cell death
(The enzymes called caspases controls of cell death and inflammation) are the effectors of apoptosis)

Question 8

How would you recognise necrosis [ particularly in wounds]?

Answer 8

• Bacterial infection
• Appearance: Leathery hard, dry or black tissue

Question 9

What are the cardinal signs of acute inflammation?

Answer 9

• Calor (heat)
• Rubor (redness)
• Tumor (swelling)
• Dolor (pain)
• Loss of function
  All need to be present to be acute inflammation

Question 10

Why do we have acute inflammation?

Answer 10

• Its a protective mechanism that aims to eliminate the source of injury or infection, remove damaged tissue, and initiate the healing process
• Immediate and early response by an organism to an injurious agent

Question 11

What is Necrosis?

Answer 11

The death of cells or tissue in the body

Question 12

What is the difference between apoptosis and necrosis?

Answer 12

Morphology - formation differs
Apoptosis - DNA fragmentation, decrease its size (blebbing), lacks inflammation
Necrosis: Have inflammation, swelling occurs, targets multiple cells

Question 13

What are the 6 types of Necrosis?

Answer 13

• Coagulative
• Colliquative (Liquefactive)
• Caseous
• Gangrene
• Fibrinoid
• Fat

Question 14

What is Neoplasia?

Answer 14

Uncontrolled, abnormal growth of cells or tissues in body

Question 15

What is Dysplasia?

Answer 15

The persistent irritation to abnormal cell (metaplasia) within tissue or organ
(may lead to nuclear atypia (abnormal cell nucleus) )
- can be reversable

Question 16

Signs of hypoxia?

Answer 16

Skin colour discolouration, wrinkly, or pale due to cell having too little oxygen (hypoxia)