Chapter 37 and 38: Gastrointestinal System

Question 1

Gastrin

Answer 1

Stimulates secretion of hydrochloric acid and pepsinogen
Increases gastric blood blood
Stimulates smooth muscle contractions

Question 2

Gastrin is released from:

Answer 2

G-cells in the stomach

Question 3

Ghrelin

Answer 3

stimulates appetite when metabolic needs are increased or during fasting states

Question 4

Ghrelin is produced mainly in the ______

Answer 4

Stomach

Question 5

Cholecystokinin (CCK)

Answer 5

Main function is the stimulation of pancreatic enzyme secretion
Stimulates contraction of GB
Potentiates secretin
Slows gastric emptying
Causes satiety

Question 6

_________ is the main source of CCK

Answer 6

Small intestine

Question 7

Secretin

Answer 7

Inhibits the release of gastrin

Stimulates the pancreas to produce large amounts of from high bicarb concentration when acidic chyme enters the duodenum

Question 8

_________ is the source of secretin

Answer 8

Small intestine

Question 9

Incretin Hormones

Answer 9

Increases insulin post-prandially
Release is glucose-dependent
Avoids hypoglycemic effect

Question 10

GLP-1 (Glucagon-Like Peptide)

Incretin Hormone

Answer 10

Suppresses glucagon release
Slows gastric emptying
Decreases appetite
Can cause weight loss

Question 11

GIP (Glucose-Dependent Insulinotropic Polypeptide)

Incretin Hormone

Answer 11

Augments the release of insulin

Question 12

Pepsin

Answer 12

Initiates the breakdown of proteins in the stomach

Inactivated in the small intestine due to increase in pH

Question 13

Prostaglandins

Answer 13

Inhibits the secretion of HCL
Promotes release of mucus
Increases bicarbonate secretion
Promotes submucosal blood flow

Question 14

Brunner’s Glands

Answer 14

Produces alkaline mucus at the duodenum to protect it from acidic chyme

Question 15

Peptidases

Answer 15

Enzymes from the small intestine that break down dipeptides to amino acids

Question 16

Amylase

Answer 16

Breaks down carbs into monosaccharides (pancreas)

Question 17

Why do carbohydrates need to be broken down in monosaccharides?

Answer 17

to be absorbed

If not, they remain osmotically active = diarrhea

Question 18

Lipase

Answer 18

Breaks down fat (pancreas)

Question 19

Trypsin

Answer 19

Breaks down proteins to dipeptides (pancreas)

Question 20

3 Main Functions of Salivary Secretions

Answer 20

1) Protection and lubrication (mucus)
2) Antimicrobial action (lysozyme)
3) Initiates the digestion of starches (ptyalin and amylase)

Question 21

Goblet Cells

Answer 21

Secretes mucus from surface stomach cells to prevent direct contact with HCL
(main reason stomach lining

Question 22

Parietal Cells

Answer 22

secretes HCL and intrinsic factor (IF)

Question 23

Intrinsic Factor (IF)

Answer 23

protein carrier that is necessary to transport Vitamin B12 to the ileum for absorption

Question 24

Chief Cells

Answer 24

secretes pepsinogen (inactive) which converts to pepsin (active) when pH is low

Question 25

G-Cells

Answer 25

secretes gastrin