Cell injury

Question 1

What are the 8 causes of cell injury?

Answer 1

GIN CHAPI
Genetic defects
Infectious agents
Nutritional imbalances
Chemical agents
Hypoxia - O2 deprivation
Ageing
Physical agents
Immunological agents

Question 2

What are the 4 intracellular mechanisms most vulnerable to cell injury?

Answer 2

Cell membrane integrity
ATP generation
Protein synthesis
Genetic apparatus integrity

Question 3

What is the difference between lethal and sub-lethal cell injury?

Answer 3

Lethal kills cell

Sub-lethal produces injury not amounting to death

Question 4

Define and give an example of hyperplasia

Answer 4

Increase in number of cells in organ

Can be pathological (e.g. carcinomas) or physiological (e.g. endometrial cell increase in the menstrual cycle)

Question 5

Define and give an example of hypertrophy

Answer 5

Increase in size of cells due to physiological (e.g. pregnancy) or pathological effects (e.g. Thyroid enlargement caused by increased secretion from parathyroid tumours)
Caused by increased functional demand or specific hormone stimulation

Question 6

Define and give an example of metaplasia

Answer 6

REVERSIBLE change where an adult cell is replaced by another
Due to physiological (e.g. puberty changing columnar to squamous epithelia in cervix) or pathological (e.g. Smoking changes lung epithelia from columnar to squamous)

Question 7

Define dysplasia

Answer 7

Pre-cancerous cells showing genetic and cytological features of malignancy without invading underlying tissue

Question 8

Define apoptosis

Answer 8

Programmed cell death
Requires ATP
Single cell dies with no inflammation

Question 9

Define necrosis

Answer 9

Confluent cell death associated with inflammation

Question 10

What is the difference between apoptosis and necrosis?

Answer 10

Apoptosis:

• may be physiological
• Requires ATP
• Not associated with inflammation

Question 11

What are the morphological changes associated with reversible injury?

Answer 11

Fatty change

Cellular swelling

Question 12

What causes apoptosis?

Answer 12

Embryogenesis
Deletion of auto-reactive T cells
Cells with irreparable damage
Cell deletion in proliferatiog populations

Question 13

What are the 4 types of necrosis?

Answer 13

Coagulative
Liquefactive
Caseous
Fat

Question 14

What factors affect response to cell injury?

Answer 14

Type of injury
Duration
Severity
Cell type