Urinary and Digestive System Flashcards Preview

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Flashcards in Urinary and Digestive System Deck (57):
1

What is the descending limb of loop of henle not permeable to?

Ions. Only permeable to water

2

What is ascending limb of loop of henle permeable to?

Ions. Not permeable to water

3

When is the collecting duct permeable to H2O?

When ADH is present

4

What is the function of the vasa recta?

maintains high sodium concentration in medulla of kidney by continually returning water to the blood stream

5

What kind of receptors are JG cells?

baroreceptors

6

What enzyme do JG cells secrete?

Renin

7

What is the function of Renin?

Activate Angiontensinogen to Angiotensin I

8

What converts Angiotensin I to Angiotensin II?

ACE

9

Why would a JG cell secrete Renin?

To increase blood pressure

10

What does Angiotensin II cause release of?

ADH

11

What receptors do macula densa have?

Chemoreceptors

12

When filtrate osmolarity is low, what do macula densa tell JG cells?

To secrete Renin and dilate afferent arterioles

13

What hormone in the urinary system increases vasoconstriction to increase blood pressure?

Angiotensin II

14

When plasma pH is to high, what is in the urine?

bicarbonate

15

When plasma pH is low, what is in the urine?

Protons

16

Function of pancreatic lipase

turn triglyceride into fatty acids and monoglycerides

17

what turns polysaccharides into disaccharides in the mouth?

Ptyalin

18

What turns polysaccharides into disaccharides in the small intestine?

Pancreatic amylase

19

What turns disaccharides into monosaccharides in the intestine?

brush border disaccharidases

20

what turns polypeptides into dipeptides and tripeptides in the stomach?

Gastric acid, Pepsin

21

What turns polypeptides into dipeptides and tripeptides in the duodenum?

Pancreatic Proteases

22

What turns dipeptides and tripeptides into single amino acids in intestine?

brush border peptidases

23

In peristalsis what prevents bolus from flowing backwards?

circular muscles

24

In peristalsis what pushes bolus forward?

longitudinal muscles

25

What are the two network of neurons in the enteric nervous system?

Myenreric plexus and submuscosal plexus

26

What is the function of the myenteric plexus?

Gut motility. Coordination of circular and longitudinal muscles

27

What is function of submucosal plexus?

Regulates enzyme secretion, gut blood flow, and ion-water balance in lumen

28

What do gastric glands secrete?

Gastric acid and Pepsinogen

29

What do goblet cells secrete?

mucous

30

What is difference between endocrine and exocrine secretion?

Endocrine don't have ducts and enter blood stream they are hormones. Exocrine secrete into ducts these are enzymes.

31

What cells in the pancreas are exocrine?

Pancreatic acinar cells

32

What cells in pancreas are endocrine?

Islets of Langerhaans. They are supplied with capillaries

33

What does parietal cells secrete?

HCl in stomach

34

What is the function of HCl in the stomach?

Destroy microorganisms, acid-catalyzed hydrolysis of dietary proteins, convert pepsinogen to pepsin

35

What cells secrete pepsinogen?

Chief cells

36

What does pepsin do?

Proteolysis

37

What is chyme?

Food mixed with gastric secretions

38

What is function of pyloric sphincter?

prevents passage of food from stomach to duodenum

39

What hormone regulates the passage of food from stomach to the duodenum?

CCK

40

What do G cell secrete?

Gastrin

41

What does gastrin stimulate?

acid and pepsin secretion. Gastric motility

42

What stimulates G cells to release gastrin?

food in stomach and parasympathetic nervous system

43

What does histamine do in digestive system?

Binds to parietal cells to stimulate acid release

44

When is histamine secreted?

In response to stomach stretching and gastrin

45

Where does absorption begin?

duodenum

46

What is function of the intestinal villus in small intestine?

capillaries absorb nutrients, lacteals transport dietary fats, contains Peyer patches which monitor GI for infection

47

What is function of bile?

Vehicle for disposal of waste and essential for digestion of fats

48

What duodenal enzyme activates trypsinogen?

enterokinase

49

What duodenal enzymes hydrolyze smallest carbohydrates and proteins?

brush border enzymes

50

What are the duodenal hormones?

CCK, Secretin, enterogastrone

51

When is CCK secreted?

When there is fat in the duodenum

52

What does CCK do?

causes pancrease to secrete more enzymes, bile release from gall bladder, and decrease gastric motility. Prevent stomach emptying

53

When is secretin secreted?

When there is acid in duodenum

54

What does secretin do?

Makes pancrease release bicarbonate to neutralize HCl

55

Duodenal pH must be what for max enzyme function?

Neutral

56

What does enterogastrone do?

decrease stomach emptying

57

What is function for colonic bacteria?

immunity and supply vitamin K