Misc Physiology

Question 1

Where does aldosterone mainly act in the kidney?
Main action(s)

Answer 1

Renal distal convoluted tubule
Na+ retention and K+ loss

Question 2

Actions of the enzymes pepsisn?

Answer 2

Bread down proteins in the stomach

Question 3

Precursor of pepsin and which cells produce it?

Answer 3

Pepsinogen
Chief cells in the gastric mucosa

Question 4

Principle function of gastrin

Answer 4

Increase H+ secretion

Question 5

Which vitamins are water soluble?

Answer 5

B & C

Question 6

What do cholera toxins activate?

Answer 6

adenylate cyclase and increase cAMP in the intestinal crypts
In crypt cells cAMP activates Cl- secretory channels

Question 7

Preload is primarily dependent on..?

Answer 7

End diastolic volume

Question 8

Which of Para and Sympathetic NS inhibit pancreatic exocrine secretion? (for fat digestion)

Answer 8

Sympathetic
(Para stimulates!)

Question 9

How is parotid gland secretions different to submandibular?

Answer 9

more watery, proteinaceous, less mucoid

Question 10

Action of the kidneys re Vit D production

Answer 10

Hydroxylation of vit D to it’s physiologically active form

Question 11

Resting potential of the SA node?

Answer 11

-60 mV

Question 12

What is the threshold potential of the SA node?

Answer 12

-40 mV

Question 13

What stimulates colonic mass movement after a meal?

Answer 13

Distension of the stomach and duodenum

Question 14

Which nerve stimulates the external anal sphincter ?

Answer 14

The motor fibres of pudendal nerve stimulates the striated muscle of the external sphincter

Question 15

Which nerve stimulates the external anal sphincter ?

Answer 15

The motor fibres of pudendal nerve stimulates the striated muscle of the external sphincter

Question 16

What causes the action potential in the SA node?

Answer 16

slow L-type Ca2+ channels

Question 17

What causes a normal anion gap in metabolic acidosis?

Answer 17

Loss of bicarbonate (causing compensatory rise in Cl- concentration so the anion gap is normal)

Question 18

3 types of capillaries

Answer 18

Continous - most selective
Fenestrated - less tight junctions and some pores
Discontinous - large gaps, permeable to RBC

Question 19

Where are continous capillaries found?

Answer 19

Lungs, muscles and CNS

Question 20

Where are fenestrated capillaries found?

Answer 20

Renal glomeruli
Endocrine glands
Intestinal villi

Question 21

Where are discontinous capillaries found?

Answer 21

Reticuloendothelial system -> Bone marrow, liver and spleen

Question 22

Haemopoesis takes place where….

1st few weeks of gestation

6 weeks to 7 months

Onwards

Answer 22

Yolk sac
Liver and spleen
Bone marrow

Question 23

MP calculation

Answer 23

Diastolic pressure + 1/3 pulse pressure

(pulse pressure = SP - DP)

Question 24

Precursor of pepsin and which cells produce it?

Answer 24

Pepsinogen
Chief cells in the gastric mucosa