Cell injury

Question 1

What is meant by reversible cell injury?

Answer 1

Cells adapt to changes in environment and return to normal once stimulus is removed

Question 2

What is meant by irreversible cell injury?

Answer 2

Permanent and cell death as a consequence

Question 3

What can cause cell stress?

Answer 3

Intensity of stimuli
Cell vulnerability

Question 4

What does the intensity of injury depend on?

Answer 4

Type of injury, duration and severity
Adaptability of the cell, nutritional status, metabolic needs

Question 5

What are some causes of cell injury?

Answer 5

Hypoxia
Physical agents
Chemicals/drugs
Pathogens
Immunological reactions
Nutritional imbalance
Genetic defects

Question 6

What is hypoxia?

Answer 6

Deficiency of oxygen

Question 7

What are causes of hypoxia?

Answer 7

Anaemia, respiratory failure

Question 8

How do hypoxic cells release energy?

Answer 8

Anaerobic mechanisms (glycolysis)

Question 9

What is Ischaemia?

Answer 9

Reduction in blood supply to tissue

Question 10

What are causes of ischaemia?

Answer 10

Blockage of arterial supply or venous drainage

Question 11

What does ischaemia result in?

Answer 11

Depletion of oxygen and nutrients

Question 12

Why is ischaemia more severe than hypoxia?

Answer 12

As anaerobic respiration will stop too

Question 13

What does mechanical trauma effect?

Answer 13

Effects cell structure and membrane

Question 14

What does extreme temperature effect?

Answer 14

Effects proteins and chemical reactions

Question 15

What are different infectious agents which cause cell injury?

Answer 15

Bacteria
Viruses
Fungi
Parasites
Protons

Question 16

What does an excess of glucose cause?

Answer 16

Osmotic disturbance

Question 17

What’s an example of a occupational hazard?

Answer 17

Asbestos

Question 18

What are examples of immunological reactions that cause cell injury?

Answer 18

Anaphylaxis
Auto-immune reactions

Question 19

What is an example of nutritional imbalance?

Answer 19

Too little - Scurvy, Rickets
Too much- Hypervitaminosis A/D

Question 20

What is scurvy?

Answer 20

Disease caused by vitamin C deficiency

Question 21

What are examples of genetic defects which cause cell injury?

Answer 21

Sickle cell anaemia
Inborn error of metabolism

Question 22

What is cloudy swelling in cells caused by?

Answer 22

When the cells are incapable of maintaining ionic and fluid homeostasis
Failure of energy dependant ion pumps in cell membrane

Question 23

What is fatty change in cells caused by?

Answer 23

Accumulation of lipid vacuoles in cytoplasm caused by disruption of fatty acid metabolism so that triglycerides cannot be released from the cell, especially in liver

Question 24

What is the common cause of fatty change in the liver?

Answer 24

Alcohol
Obesity
Diabetes

Question 25

What is necrosis?

Answer 25

Cell death due to some form of pathology

Question 26

How are cell remains from necrosis removed?

Answer 26

Phagocytosis

Question 27

What response occurs in surrounding tissues from necrosis?

Answer 27

Inflammatory response

Question 28

What is pyknosis?

Answer 28

When the nucleus shrinks

Question 29

What is karyorrhexis?

Answer 29

When the nucleus splits into fragments

Question 30

What is karyolysis?

Answer 30

Nucleus is digested by endonucleases

Question 31

What is a cytoplasmic change in necrotic cells?

Answer 31

Appears paler because swollen More pink due to denaturation of cytoplasmic structural and enzyme proteins

Question 32

What are different types of necrosis?

Answer 32

-coagulative necrosis -Liquefactive necrosis -Caseous necrosis -Gangrenous necrosis -Fat necrosis -Fibrinoid necrosis

Question 33

What is liquefactive necrosis?

Answer 33

When cells are broke down to liquid state (PUS)

Question 34

Where is fibrinoid necrosis?

Answer 34

Necrosis seen in immune reactions in blood vessels

Question 35

What are the effects of necrosis?

Answer 35

Inflammation Cell remains are phagocytosis Necrotic area replaced with a scar

Question 36

What is apoptosis?

Answer 36

Genetically programmed cell death

Question 37

What are differences between apoptosis and necrosis?

Answer 37

Necrosis causes inflammation and doesn't require energy, apoptosis doesn't cause inflammation and does require energy

Question 38

What are pathological triggers of apoptosis?

Answer 38

Hypoxia and ischaemia Viral infection (CD8+ contain enzymes that induce apoptosis) DNA damage

Question 39

What are caspases?

Answer 39

Activated enzymes which trigger apoptosis

Question 40

What are physiological roles of apotosis?

Answer 40

Deletion of cell populations during embryogenesis Cell deletion in proliferating cell populations to maintain numbers Deletion of inflammatory cells after an inflammatory response Deletion of self reactive T cells in thymus

Question 41

What does apoptosis look like in a cell?

Question 42

What can an accumulation of cholesterol in cells cause?

Answer 42

Atherosclerosis

Question 43

What is amyloid?

Answer 43

A fibrillar protein material which is deposited as a result of pathologic processes leading to increased production of these proteins

Question 44

What can amyloid be stimulated by?

Answer 44

Chronic inflammation Multiple myeloma Ageing Drug abuse

Question 45

What diseases can amyloid cause?

Answer 45

Alzheimer's

Question 46

What are examples of endogenous pigmentation?

Answer 46

Melanin Bilirubin

Question 47

What are examples of exogeneous pathological pigementation?

Answer 47

Carbon (inhaled soot/smoke) Tattoos Heavy metal salts (lead)

Question 48

What is dystrophic calcification?

Answer 48

Deposits of calcium phosphate in necrotic tissue

Question 49

What is metastatic calcification?

Answer 49

Deposits of calcium in normal, vital tissue

Question 50

What are causes of hypercalcaemia?

Answer 50

-Increased level of PTH -Destruction of bone tissue -Excess vitamin D -Renal failure