Abnormalities of growth / celullar adaptation

Question 1

Give an example of cells which do not need to adapt as the are able to survive severe metabolic stress without harm?

Answer 1

Fibroblasts

Question 2

Give an example of cells with are able to adapt easily

Answer 2

Epithelial cells

Question 3

Give an example of cells that are unable to adapt?

Answer 3

Cerebral neurons

Question 4

How to cells respond to increased demand?

Answer 4

1) increase size of cells (hypertrophy)

2) increased number of cells (Hyperplasia)

Question 5

What is involved in subcellular hypertrophy and hyperplasia?

Answer 5

1) increased size and number of organelles

Question 6

What is the process of reduction in size of organ or tissue by decrease in cell size and number?

Answer 6

Atrophy

Question 7

What physiological situations do we see atrophy?

Answer 7

• embryogenesis

- uterus after pregnancy / menopause.

Question 8

When do we see pathological atrophy?

Answer 8

• decreasede workload
• loss of innervation
• diminished blood supply
• loss of endocrine stimulation

Question 9

What are the mechanisms of atrophy?

Answer 9

1) reduction in volume of individual cells

2) Death of individual cells (apoptosis)

Question 10

What is Involution?

Answer 10

Involution is PHYSIOLOGICAL atrophy by apoptosis

Question 11

What is ageneis?

Answer 11

failure of formation of an embryonic cell mass

Question 12

What is aplasia?

Answer 12

Failure to differentiate to organ specific tissue

Question 13

What is dysagenesis?

Answer 13

failure of structural organisation of tissues into organs

Question 14

What is hypoplasia?

Answer 14

failure of growth of organ to full size

Question 15

What is metaplasia?

Answer 15

Transformation of one differentiated cell type into another

Question 16

Where do we see metaplasia as part of the physiological process?

Answer 16

Uterus transforms through pre-puberty, puberty, pregancy, menopause

Question 17

Where do we see pathological metaplasia?

Answer 17

1) Cigarette smoke causes epithelium to change from pseudostratified ciliated bronchial to sqaumous epithelium.
2) Bladder calculus/schistomosiasis/longstanding catheter.
3) Acid reflux causes the oesophageal squamous epithelium to change to columnar (glandular) epithelium.

Question 18

What is dysplasia?

Answer 18

the earliest manifestion of multistage process of neoplasia

Question 19

True or false :

Adaptations are reversible changes

Answer 19

TRUE

Question 20

True or fale:

Dysplasia is reversible

Answer 20

FALSE