Cell Stress, Adaptation and Death

Question 1

Describe the main differences between apoptosis & necrosis

Answer 1

Apoptosis occurs physiologically and pathologically while Necrosis is only pathological
Apoptosis is the programmed death of cells while necrosis is the result of sudden sever stress not allowing time for adaption
A single cell can die by apoptosis, a necrotic cell kills neighbouring cells
Apoptosis is active requiring energy necrosis is passive
Apoptosis does not stimulate inflammation, necrosis does

Question 2

What determines whether a stimulus causes atrophy or infarction?

Answer 2

Slow acute stress/stimulus allows time for adaptation and atrophy
Sudden sever stimulus doesn’t allow for adaption so the cell undergoes necrosis causing an infarction and inflammation

Question 3

What effect does ageing have on cells & organs?

Answer 3

Damaged cells usually end up dyeing at older ages instead of repairing
less cells results in a decrease in function
Ageing is associated with free radicals which potentiate mutation

Question 3

What effect does ageing have on cells & organs?

Answer 3

Damaged cells usually end up dyeing at older ages instead of repairing
less cells results in a decrease in function
Ageing is associated with free radicals which potentiate mutation

Question 4

What is meant by labile, stable & permanent cells, give some examples.

Answer 4

Labile cells are continuously dividing
Stable cells divide with stimulus ie. an injury
Permanent cells are non-dividing (CNS neurons, Cardiac, skeletal myocytes)

Question 5

Define ischaemia, hypoxia/hypoxemia, necrosis, infarction, autophagy, apoptosis, atrophy, hypertrophy, hyperplasia & metaplasia.

Answer 5

Ischaemia - lack of blood supply
Hypoxia - lack of O2
Hypoxaemia - lack of 02 in the blood
Necrosis - pathological cell death
Infarction - area of necrosis
Autophagy - Active self eating/ shrinkage of cells
Apoptosis - Decrease in cell number via programmed cell death (physiological or pathological)
Atrophy - Decrease in cell size
Hypertrophy - increase in cell size
Hyperplasia - increase in cell number
Metaplasia - Change in cell structure and function (change from 1 normal cell type to another)

Question 6

Give some examples of cell types that are considered epithelial, connective & ‘other’.

Answer 6

Epithelial - Stratified Squamous, glandular epithelium (columnar),
Connective - Collagen, Bone, Fat, muscle, Endothelium (lining of blood vessels)
Other - Mesothelial/mesothelium, CNS/PNS, Germ cells

Question 7

What cellular adaptation(s) can lead to an increase in the overall size of an organ?

Answer 7

Hypertrophy and Hyperplasia

Question 8

What form of cell death occurs during normal embryogenesis?

Does this form of cell death cause inflammation?

Answer 8

Apoptosis

Apoptosis doesn’t cause cell death

Question 9

Which form of cell death causes inflammation?

Answer 9

necrosis

Question 10

What is the definition of metaplasia?

Answer 10

The change of one normal cell type to another in order to adapt to the stresses and workload of their environment

Its really important that cells can adapt and change to a changed environment

Question 11

Give an example of a non-dividing cell type

Answer 11

CNS neurons
Cardiac
Skeletal myocytes

Question 12

Which one of the following statements is TRUE?
Atrophy is a combination of autophagy & necrosis.
Atrophy is a passive process.
Autophagy is a form of cell death.
Apoptosis only occurs in disease.
Atrophy may not be reversible.

Answer 12

Atrophy may not be reversible.

For example in a permanent tissue like cardiac tissue (heart)

Question 13

Which one of the following statements is false?
Metaplasia results in cells that are genetically and phenotypically normal.
Hyperplasia results in an increase in cell number.
Hypertrophy is the opposite of autophagy.
Apoptosis only occurs in disease.
Atrophy is not always reversible.

Answer 13

Apoptosis only occurs in disease.

Question 14

What is the term given to a secretory epithelial cell?

Answer 14

Glandular epithelial

Question 15

Which type of epithelium is the best at withstanding physical stress?

Answer 15

Stratified squamous epithelial

Question 16

What cellular adaptation will occur in a heart that is forced to work harder?

Answer 16

Hypertrophy

Question 17

If the blood supply to the heart is suddenly and completely stopped, what form of cell death will occur?
Will there be an inflammatory response in this example?

Answer 17

Necrosis

Yes

Question 18

When cells undergo metaplasia are they considered normal or abnormal?

Answer 18

Normal

Question 19

Which one of the following statements is true?
Metaplasia is not a reversible adaptation.
Hyperplasia results in an increase in cell size.
Autophagy is the opposite of hypertrophy.
All cell types are able to undergo all of the adaptations that we have learned about .
An infarct is an area of apoptosis.

Answer 19

Autophagy is the opposite of hypertrophy.

Question 20

Which one of the following statements is False?
Metaplasia is a reversible adaptation.
Skeletal muscle that if forced to work harder usually undergoes hypertrophy.
Apoptosis is the opposite of hyperplasia.
All cell types are able to undergo all of the adaptations that we have learned about.
An infarct always causes an inflammatory response in a living person.

Answer 20

All cell types are able to undergo all of the adaptations that we have learned about.