Cell Injury and Fate

Question 1

Two types of injury?

Answer 1

Lethal- produces cell death

Sublethal- produces potentially reversible injury

Question 2

8 causes of cell injury?

Answer 2

• Oxygen deprivation
• Chemical agents
• Infectious agents
• Immunological reactions
• Genetic defects
• Nutritional imbalances
• Physical agents
• Aging

Question 3

Factors affecting cellular response

Answer 3

Type of injury
Severity
Duration

Question 4

4 vulnerable intracellular systems?

Answer 4

1. Cell membrane integrity
2. ATP generation
3. Protein synthesis
4. Integrity of genetic apparatus

Question 5

Infarction?

Answer 5

Cell death due to ischaemia

Question 6

Atrophy?

Answer 6

Shrinkage in cell or organ size

Question 7

Hypertrophy?

Answer 7

Cells and organs becoming larger in size. Can be physiological (normal) or pathological. Caused by increased functional demand or specific hormone stimulation

Question 8

Hyperplasia?

Answer 8

Increase in number of cells to increase organ size

Physiological hyperplasia can be either hormonal or compensatory. Pathological hyperplasia is due to excess hormones or growth factors

Question 9

Metaplasia?

Answer 9

Reversible change in which one adult cell type is replaced by another

Question 10

Dysplasia?

Answer 10

Precancerous cells which show genetic and cytological features or malignancy but not invading the underlying tissue

Question 11

2 changes associated with reversible injury?

Answer 11

• Fatty change

- Cellular swelling (ballooning)

Question 12

Necrosis?

Answer 12

Confluent cell death associated with inflammation

Question 13

4 changes associated with irreversible injury

Answer 13

• Coagulative necrosis- structure becomes fixed and solid
• Liquefactive necrosis- where tissue becomes liquefied
• Caseous necrosis- structure becomes oozy and structureless
• Fat necrosis- digestive enzymes activated in the pancreas rather than duodenum so fat is broken down. Free fatty acids then bind to calcium to form white lumps. Can form on breasts as well

Question 14

Necrosis vs apoptosis

Answer 14

Apoptosis can be physiological, is an active energy dependent process and is not associated with inflammation

Question 15

Apoptosis?

Answer 15

Programmed cell death

Question 16

5 causes of apoptosis?

Answer 16

• Embryogenesis
• Deletion of auto-reactive T cells in the thymus
• Hormone-dependent physiological involution
• Cell deletion in proliferation populations
• A variety of mild injurious stimuli that cause irreparable DNA damage that, in turn, triggers cell suicide pathways

Question 17

Necroptosis

Answer 17

Programmed cell death with inflammation. Can be caused by viral infection