Lecture 2 Injuries to cells

Question 1

Define hyperplasia

Answer 1

Increase in number of cells.

Question 2

Physiological example of hyperplasia?

Answer 2

Menstrual cycle

Question 3

Pathological example of hyperplasia?

Answer 3

Endometrial hyperplasia if hormone stimulus persists

Question 4

Define hypertrophy

Answer 4

Increase in the size of cells

Question 5

Physiological example of hypertrophy?

Answer 5

Body builders

Question 6

Pathological example of hypertrophy?

Answer 6

Heart in hypertension

Question 7

Define Mataplasia

Answer 7

When one adult cell type is replaced by another adult cell trype

Question 8

Example of metaplasia?

Answer 8

Chronic gastro-oesophageal reflux

Question 9

Define atrophy

Answer 9

Shrinkage of cell size by loss of substance

Question 10

Why atrophy happens?

Answer 10

↓ workload. ↓blood supply. Inadequate nutrition. ↓hormone stimulation. Ageing.

Question 11

Morphology of reversible cellular injury?

Answer 11

Cellular swelling and fatty change.

Question 12

Define necrosis

Answer 12

Damage to membrane allowing enzymes to digest cell.

Question 13

Necrosis pathological or physiological

Answer 13

Always pathological

Question 14

4 types of necrosis

Answer 14

Coagulation, liquefactive, caseous, fat.

Question 15

Define apoptosis

Answer 15

Programmed cell death pathway. Both pathological and physiological.

Question 16

How does apoptosis occur?

Answer 16

Cells activate enzymes that degrade cells own DNA and proteins -> death/deprived growth factors. Membrane remains intact, no leaks, phagocytosis removes bits of cell.

Question 17

Physiological or pathological apoptosis? Embryogenesis

Answer 17

Physiological

Question 18

Physiological or pathological apoptosis? Involution of hormone dependent tissues when deprived of hormone.

Answer 18

Physiological

Question 19

Physiological or pathological apoptosis? Elimination of cells who have served their purpose.

Answer 19

Physiological

Question 20

Physiological or pathological apoptosis? Killing ?harmful cells

Answer 20

Physiological

Question 21

Physiological or pathological apoptosis? DNA damage

Answer 21

Pathological

Question 22

Physiological or pathological apoptosis? Accumulation of misfolded proteins

Answer 22

Pathological

Question 23

Physiological or pathological apoptosis? Atrophy in parenchymal organs after duct obstruction.

Answer 23

Pathological

Question 24

Physiological or pathological apoptosis? Cell death induced by cytotoxic T cells

Answer 24

Pathological

Question 25

Apoptosis results from the activation of

Answer 25

Caspases

Question 26

Mitochondrial pathway…

Answer 26

Intrinsic pathway

Question 27

Fas (death) receptor pathway…

Answer 27

Extrinsic pathway

Question 28

Cell injury by ATP depletion

Answer 28

Occurs from: ↓oxygen and nutrient supply, mitochondrial damage, poisons. Effects: ATP dependent Na2+ pumps, ^lactic acid, Xcalcium pumps& protein damage.

Question 29

Mitochondrial damage

Answer 29

Occurs from: hypoxia, chemical poisons, radiations. Effects: Fail to produce ATP & free radicals

Question 30

Influx of Ca2+

Answer 30

Occurs from: ischaemia & poisons. Effects: ^intracellular Ca2+ -> enzyme activation -> damage to cellular components. APOPTOSIS.

Question 31

Oxidative stress

Answer 31

Occurs from: ^free radicals. Removed by antioxidants. Effects: damage proteins, fat, DNA & create more of themselves.

Question 32

DNA protein damage

Answer 32

Occurs from: radiation injury/oxidative stress. APOPTOSIS.

Question 33

Defects in membrane permeability

Answer 33

Effects: ↓phospholipid synthesis (↓ATP). O2 free radicals and lipid breakdown. NECROSIS

Question 34

Intracellular accumulation of abnormal material examples

Answer 34

Fat in hepatocytes (liver cells) from alcohol use. Cholesterol in SM in atherosclerosis. Protein in alzheimer’s and parkinson’s disease.

Question 35

Damage to genes controlling DNA repair ->

Answer 35

susceptible to further change

Question 36

Neoplastic

Answer 36

New growth