cellular adaptation

Question 1

myometrial growth induced by hormones during pregnancy is due to (hypertrophy/hyperplasia)?

Answer 1

hypertrophy: lay down more myofibrils →↑ muscle size →↑ muscle strength

Question 2

muscle growth induced by exercise is due to (hypertrophy/hyperplasia)?

Answer 2

hypertrophy: lay down more myofibrils →↑ muscle size →↑ muscle strength

Question 3

myocardial growth induced by chronic HTN (↑afterload) is due to (hypertrophy/hyperplasia)?

Answer 3

hypertrophy: ↑LV strength →↑LV less compliant/stiff → LV can’t relax →diastolic heart failure

Question 4

growth of gland tissue of breast induced by estrogen is due to (hypertrophy/hyperplasia)?

Answer 4

hyperplasia

Question 5

endometrial growth induced by estrogen (and no progesterone) is due to (hypertrophy/hyperplasia)?

Answer 5

hyperplasia

Question 6

liver regeneration is due to (hypertrophy/hyperplasia)?

Answer 6

hyperplasia: quiescent hepatocytes come out of Go → G1 and enter the cell cycle → divide a couple times → go back to Go, endothelial cells will also regenerate in the liver

Question 7

what happens to lower esophagus in response to chronic GERD

Answer 7

intestinal metaplasia = Barret’s esophagus

squamous epithelium → columnar epithelium (in stomach, intestine) →↑ risk of esophageal adenocarcinoma

Question 8

is metaplasia reverisble/irreverisble?

Answer 8

reversible

Question 9

complication of Barret’s esophagus

Answer 9

esophageal adenocarcinoma

Question 10

what happens to trachea/bronchus in response to smoke?

Answer 10

metaplasia: ciliated columnar (produces mucus, traps toxins) → squamous metaplasia →↑ risk of respiratory infections + cancer

Question 11

type of cellular adaptation in which local stem cells are induced to make a new cell type and replace the current stem cell type due to an ongoing stressor

Answer 11

metaplasia

Question 12

lipofuscin granules

Answer 12

sign of atrophy or normal aging: partial lipid oxidation (degradation) by oxygen free radical species
yellow/brown residual body inside macrophages

Question 13

pathophysiology of atrophy

Answer 13

some stimuli causes ↓ cell size and/or number of cells which causes:
↓cellular organelles
↓metabolic activity
↓protein synthesis/↑protein degradation via ubiquitin proteosome pathway
autophagy
lysosomal degradation of cellular components

Question 14

what is it called when a cell eats its own organelles to survive

Answer 14

autophagy

Question 15

↓ endogenous hormones (estrogen - post-menopausal) is called

Answer 15

atrophic vaginitis: thin, dry

Question 16

↓ innervation (motor neuron damage) can cause

Answer 16

atrophy

Question 17

↓blood flow/nutrients can cause

Answer 17

atrophy

Question 18

↑ pressure (nephrolithiasis) can cause

Answer 18

atrophy

Question 19

↑ exogenous hormones (thryotoxicosis, steroid use) can cause

Answer 19

atrophy

Question 20

what is a long non-coding DNA sequence on the end of chromosomes which shortens with every cell division (mitosis)

Answer 20

telomeres: causes cells to have a limit to how many times they can divide - when end of chromosome exposed = DNA damage → cell cycle arrested

Question 21

RNA dependent DNA polymerase that adds DNA to 3’ end of chromosomes which elongates the telomeres

Answer 21

telomerase

Question 22

does somatic tissue have telomerase

Answer 22

NO

Question 23

do stem cells + germ cells have telomerase

Answer 23

YES

Question 24

compensatory growth of muscle fibers is due to (hypertrophy/hyperplasia)?

Answer 24

hypertrophy

Question 25

best way to prolong life span?

Answer 25

↓ caloric restriction which activates DNA repair enzymes - cells last longer