L2 cell adaptation to stress

Question 1

what is cellular adaptation?

Answer 1

adaptations are reversible changes in the cell’s shape, size, function, metabolic activity, phenotype, etc, in response to changes in its environment.

Question 2

adaptive responses of cells to injury?

Answer 2

-atrophy
-hypertrophy
-hyperplasia
-metaplasia

Question 3

apoptosis is _____ and necrosis is ______

Answer 3

1. programmed cell death
2. premature cell death

Question 4

define
-atrophy
-hypertrophy
-hyperplasia
-metaplasia

Answer 4

1. decrease in cell size
2. increase in cell size
3. increase in cell number
4. different cell type

Question 5

types of atrophy

Answer 5

1. physiologic
2. pathologic

Question 6

physiologic atrophy examples

Answer 6

1. thymus gland (embryonic)
2. thyroglossal duct (embryonic)
3. uterus after menopause

Question 7

pathologic atrophy can be local or generalized.
common causes? (6)

Answer 7

1. decreased workload (atrophy of disuse)
2. loss of blood supply
3. loss of nerve supply (denervation atrophy)
4. pressure atrophy
5. inadequate nutrition
6. loss of endocrine stimulation

Question 8

note on disuse atrophy

Answer 8

-due to decreased workload
-eg. limbs in plaster cast or patient under prolonged bed rest
-REVERSIBLE, skeletal muscles back to normal after usage

Question 9

note on denervation atrophy

Answer 9

-nerve supply to skeletal muscles gets cut off
-they’re dependent on nerves for proper functioning
-if nerve supply gets cut off, muscles rapidly atrophy

Question 10

1. atrophy due to diminished blood supply
2. inadequate nutrition atrophy

Answer 10

1. -seen in atherosclerotic brain in late adult life. widening of brain gyri
   -arterial occlutive disease
2. -extreme protein malnourishment- marasmus
   -cachexia in cancer and chronic inflammatory diseases

Question 11

atrophy due to loss of endocrine stimulation

Answer 11

-loss of estrogen stimulation in young females leading to atrophy of breast, endometrium and vaginal epithelium
-it is pathologic since its in a young female
-if it were after menopause it’d be considered physiologic

Question 12

pressure atrophy

Answer 12

1. eg. brain tumor (enlarging benign) will grow and put pressure on the brain causing surrounding areas to atrophy

Question 13

examples of physiologic hyperplasia

Answer 13

1. breast enlargement during puberty
2. inc. in uterus size during pregnancy
3. compensatory hyperplasia in the case of liver transplant (liver regeneration) and bone marrow hyperplasia after blood donation

Question 14

examples of pathologic hyperplasia

Answer 14

1. benign nodular hyperplasia, prostate enlargement in males
2. warts due to viruses like HPV
3. endometrial hyperplasia due to circulating estrogen

Question 15

physiologic hypertrophy examples

Answer 15

1. uterus and breast in pregnancy
2. skeletal muscles in bodybuilding

Question 16

metaplasia definition

Answer 16

reversible change in which one cell type is replaced by another, so function and shape are different

Question 17

pathologic metaplasia example

Answer 17

in smokers, trachea and bronchi which have ciliated columnar cells get replaced by stratified squamous epithelial cells

Question 18

barrett esophagus note

Answer 18

esophageal squamous epithelium gets replaced by intestinal like columnar cells due to refluxed gastric acid.