Cell adaptations to injury

Question 1

What are the stages in the cellular response to an injury/stress/insult?

Answer 1

Normal cell (Homeostasis)
Stress
Adaptation
Reversible Injury
Irreversible injury
Cell death

Question 2

What is a reversible injury?

Answer 2

The process in which a cell receives a stress is able to respond to it by adapting and then is able to go back to normal.

Question 3

What is an irreversible injury?

Answer 3

The process by which a cell receives too big of a injury/stress that it cannot adapt to the change and therefore cannot go back to normal

The inevitable outcome of an irreversible injury is cell death

Question 4

What are the key forms of cellular adaptations?

Answer 4

Hypertrophy
Hyperplasia
Atrophy
Metaplasia

Question 5

What is Hypertrophy?

Answer 5

Increase in size of cells
Synthesis of structural proteins

Question 6

What are 2 examples of Hypertrophic adaptations?

Answer 6

Increased size of the uterus during pregnancy (Physiological adaptation)

Hypertrophic Cardiomyopathy (Pathological adaptation)

Question 7

What is Hyperplasia?

Answer 7

Cell replication, if population is able to
Occurs with Hypertrophy
Hormonal or Compensatory

Question 8

What influences whether a cell can undergo Hyperplasia?

Answer 8

Where they are situated
What type of cell they are

Question 9

What are labile cells?

Answer 9

Constant active self -renewal
E.g. Skin
Gastrointestinal mucosa
Haemopoietic cells

Question 10

What are Stable cells?

Answer 10

Low level of renewal with capacity to replace cells
E.g. Liver
Renal tubular cells
Glial cells in the CNS

Question 11

What are permanent cells?

Answer 11

No capacity to replace cells
E.g. Adult neurons
Renal glomeruli
Retinal epithelial cells