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Flashcards in Secretions of the GI System Deck (62)
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1
Q

Salivary secretions are regulated by cranial nerves ___ and ____

A

7 + 9

2
Q

What are the three salivary glands?

A

Parotid + Submandibular + Sublingual

3
Q

What initiates carb. digestion?

A

Alpha amylase

4
Q

What initiates fat digestion?

A

Lingual lipase

5
Q

What is found in saliva that acts as a major lubricant?

A

Mucous

6
Q

What chelates iron and is needed for bacterial replication?

A

Lactoferrin

7
Q

What does alpha amylase initiate?

A

Carb. digestion

8
Q

What does lingual lipase initiate?

A

Fat digestion

9
Q

What does lactoferrin do?

A

Chelates iron; iron is needed for bacterial replication

10
Q
Which of following is not associated with salivary secretion?
A. Salivatory nucleus
B. Lingual lipase
C. Vagus nerves
D. Parotid gland
A

C. Vagus nerves

11
Q

What secretes HCl?

A

Parietal cells

12
Q

What does pepsin do?

A

Contributes to protein digestion

13
Q

What is the function of HCl?

A

To denature dietary proteins + kill ingested microorganisms

14
Q

What does gastric lipase do?

A

Contributes to fat digestion

15
Q

What are intrinsic factors in gastric juice?

A

A glycoprotein necessary for Vit. B12 absorption

16
Q

What kind of pump does the gastric acid secretion use?

A

Proton pump; pumps H+ from cytoplasm into stomach lumen for K+

17
Q

How does Cl- get into parietal cells?

A

Via the Cl/HCO3 exchange

18
Q

Parietal cells contain receptors for what that stimulate acid secretion?

A
  1. ACh
  2. Gastrin
  3. Histamine
19
Q

There are several pathways to stimulate gastric acid secretion. What are they?

A
  1. Vagus nerve via ACh
  2. Endocrine stimulation for gastrin from G cells
  3. Paracrine stimulation from histamines
20
Q

What happens to gastric acid secretion if the vagus nerve via ACh is stimulated?

A

Calcium increases

21
Q

What happens to gastric acid secretion if gastrin is stimulated?

A

Endocrine stimulation, Calcium increases

22
Q

What happens to gastric acid secretion if histamines are released?

A

Paracrine stimulation, increases cAMP

23
Q

What does secretin do?

A

Stimulates production of bicarbonate

24
Q

Where is secretin produced?

A

Duodenum

25
Q

What cells produce secretin?

A

S cells

26
Q

When gastric pH is low, H+ (promotes/inhibits) G cells

A

inhibits

27
Q

When gastric pH is low, Somatostatin levels are (increased/decreased) and (promote/inhibit) G cells

A

increased + inhibit

28
Q

When gastric pH is low, secretin is (produced/inhibited)

A

produced

29
Q

Why is prostaglandin important?

A

Part of the secretion of mucus

30
Q

Where is prostaglandin E2 produced?

A

Stomach

31
Q

Prostaglandin E2 is an antagonist to what in the parietal cells?

A

Histamine

32
Q

Prostaglandin E2 is an (agonist/antagonist) to histamine in the parietal cells?

A

antagonist

33
Q

Prostaglandin E2 (promote/inhibit) production of cAMP

A

inhibit

34
Q

Because NSAIDS inhibit prostaglandins , what do they do to gastric acid secretion?

A

Increases it

35
Q

What can occur as a result of chronic use of NSAIDS?

A

Erosive gastritis

36
Q

Mucus glands are (stimulated/inhibited) by sympathetic stimulation

A

inhibited

37
Q

The enterocytes in the crypts do what?

A

Secrete large amounts of water/electrolytes

38
Q

The enterocytes over the surfaces of the villi do what?

A

Reabsorb the water/electrolytes along the end products of digestion

39
Q

The mucus glands are inhibited by (sympathetic/parasympathetic) stimulation

A

Sympathetic

40
Q

The enterocytes that cover the villi, contain digestive enzymes that digest specific food substances while they are being absorbed through the epithelium and one of which is peptidase. What does it do?

A

Splits small peptides into AA

41
Q

The enterocytes that cover the villi, contain digestive enzymes that digest specific food substances while they are being absorbed through the epithelium and some are sucrase, maltase, isomaltase, and lactase. What does it do?

A

Splits disaccharides into monosaccharides

42
Q

The enterocytes that cover the villi, contain digestive enzymes that digest specific food substances while they are being absorbed through the epithelium and one of which is intestinal lipase. What does it do?

A

Splits neutral fats into glycerol and FA

43
Q

Which of the following statements is False?

A. NSAIDs inhibit prostaglandin formation and increase gastric acid secretion.
B. The production of alkaline mucus in small intestines, in part, is stimulated by the vagus nerves
C. Enterocytes in the intestinal villi secrete peptidases for breaking down carbohydrates
D. Enterocytes in the intestinal crypts secrete water.

A

C. Enterocytes in the intestinal villi secrete peptidases for breaking down carbohydrates

44
Q

As chyme goes from stomach to small intestine, what must be neutralized quick?

A

Acid; this is done via pancreas which secretes alkaline fluid

45
Q

What must be broken down further after it passes the stomach?

A

Macromolecules; fats + proteins + starch; pancreas will produce enzymes that break this down

46
Q

What enzyme hydrolyzes starches, glycogen, and most other carbs (except cellulose)?

A

Pancreatic amylase

47
Q

When there is a presence of acid, ______ stimulation potentiate the effects of secretin

A

Cholinergic

48
Q

When there is a presence of acid, ______ stimulates ductal bicarbonate production

A

Secretin

49
Q

When there is a presence of acid, ____-______ stimulates acinar enzyme secretion

A

CCK-cholecystokinin

50
Q

Cholinergic, secretin, CCK-cholecytokinin secretion are triggered by the presence of _____

A

acid

51
Q

Secretion of bile is through the _____ tract

A

biliary

52
Q

Biles facilitates digestion of fats by emulsification and solubilization of fats. This is known as the _____ action

A

Detergent

53
Q

What does the bile salts do to the surface area of fats?

A

Increase SA

54
Q

Bile salts form mixed micelles and enhance the absorption of lipids by epithelial cells in the _____

A

ileum

55
Q

Bile is actively secreted by what cell?

A

Hepatocytes from cholesterol

56
Q

50% cholesterol eliminations is due to what?

A

Synthesizing bile salts

57
Q

The recirculation of bile is known as what?

A

Enterohepatic circulation

58
Q

(T/F) Bile amount is typically big enough to assimilate the lipid content of a typical meal

A

False, not enough. Entire bile pool is recirculated 2+ times

59
Q

A. ACh,
B. gastrin,
C. histamine,
D. secretin

Vagus nerves_____
G cells_____
CCK receptor_____
H2 receptor ______

A

asd

60
Q

A. ACh,
B. gastrin,
C. histamine,
D. secretin

Bicarbonate production______
cAMP activation _______
ECl cells _______
Endocrine ______

A

adf

61
Q

A. ACh,
B. gastrin,
C. histamine,
D. secretin

Paracrine_______
Calcium-dependent-pathway________
Parietal cells______
Increases gastric secretion_______

A

adsf

62
Q

What do trypsin and chymotrypsin do?

A

Splits Proteins