Cellular Adaptations and Cell Damage

Question 1

What proliferative capacity do cells have?

Answer 1

Labile - continuous division
Stable - some division
Permanent - almost no division

Question 2

Name 3 ways cells can adapt to stress

Answer 2

Change:

• Cell number
• Cell size
• Cell type

Question 3

Define Hyperplasia

Answer 3

Increase in the number of cells within a tissue

Cells must be stable or labile (not permanent)

Question 4

Give 2 examples of physiological (normal) Hyperplasia

Answer 4

Hormonal - Endometrium

Compensatory - proliferation after hepatectomy

Question 5

Give 2 causes of pathological Hyperplasia

Answer 5

Excessive hormone/growth factor stimulation
Chronic irritation

May occur alongside hypertrophy
Some increased risk of tumour development

Question 6

Define Hypertrophy

Answer 6

Increase in cell size
Common when permanent cells have increased demands
More cellular structural proteins produced (not just cell swelling)

Question 7

Give 2 examples of physiological (normal) Hypertrophy

Answer 7

Increased functional demand - Mechanical and skeletal muscle

Hormonal/ growth factor - Uterine muscle in pregnancy

Question 8

Give an example of pathological hypertrophy

Answer 8

Cardiac muscle:

Left ventricle primarily in Hypertension, Aortic stenosis

Question 9

Define Atrophy

Answer 9

Shrinkage in cell size by loss of cell substance

Question 10

What are some causes of Atrophy?

Answer 10

Reduced workload
Loss of nerve supply
Reduced blood supply
Inadequate nutrition
Loss of endocrine stimulation
Ageing

Question 11

Define metaplasia

Answer 11

Reversible change from one adult cell type to another adult cell type

Question 12

Give an example of physiological (normal) metaplasia

Answer 12

Glandular to squamous epithelium in the pubertal cervix

Question 13

Give an example of pathological metaplasia

Answer 13

Squamous to glandular in reflux oesophagitis i.e. Barrett’s

Question 14

Define dysplasia

Answer 14

Premalignant condition
Increased cell growth
Cellular atypia
Altered differentiation
Can range from mild to severe
Sites: Cervix, Bladder, Stomach/oesophagus

Question 15

Define Neoplasia

Answer 15

Abnormal growth of cells which persists after initiating stimulus has been removed
(Cell growth has escaped from normal regulatory mechanisms)
Can be benign/malignant

Question 16

Outline the 6 noxious stimuli and give an example of a clinical manifestation for each

Answer 16

Oxygen deprivation - Ischaemia
Chemical - retinopathy in premature babies
Infections - (literally any infective agent)
Physical - frostbite
Immune - anaphylaxis
Nutritional insufficiency - Marasmus (malnourishment in children)

Question 17

Outline the mechanisms that initiate cell death.

Answer 17

Depletion of ATP
Mitochondrial Damage
Loss of Ca+ Homeostasis
Oxidative stress (ROS)
Free Radicals (UV light)
Defects in Membrane Permeability

Question 18

What are the two types of cell death?

Answer 18

Necrosis - ALWAYS PATHOLOGICAL

Apoptosis - Can be pathological or physiological (normal)