Gastric function

Question 1

5 gastric functions

Answer 1

1. reservoir
2. begins digestion (breaks food into small 2mm)
3. delivers food to duodenum
4. produces gastric juice
5. protects against micro-organisms

Question 2

3 muscle functions of stomach

Answer 2

1. receptive relaxation
2. trituration - making chyme
3. emptying

Question 3

where is cutoff to 2 different glandular mucosa of stomach

Answer 3

between body and antrum

Question 4

2 main types of stomach glands

Answer 4

1. oxyntic - body and fundus

2. plyoric

Question 5

6 cell types of oxyntic glands - and secretions

Answer 5

1. surface cells
2. mucous neck cells
3. enterochromaffin cells - histamine
4. D cells - somatostatin
5. parietal cells - acid
6. chief cells - pepsinogin

Question 6

what is a paracrine cell

Answer 6

cell that affects the actions of the cell next to it

Question 7

special cell of pyloric gland

Answer 7

G cell - gastrin

Question 8

how does parietal cell work

Answer 8

CO2 + H2O become H2CO3 > H + HCO3-

H is secreted into stomach by K/H ATPase and HCO3 into blood

Question 9

3 main signals of gastric acid production

Answer 9

1. gastrin
2. histamine
3. acth

Question 10

function of histamine

Answer 10

produced by ECL cell to tell parietal cell to secrete acid

Question 11

function of gastrin (2)

Answer 11

1. directly tell parietal cell to secrete acid

2. tells ECL to secret histamine

Question 12

function of ACTH (3)

Answer 12

1. tells parietal cell to secrete acid directly
2. stims G cells
3. stims ECL cells

Question 13

what stims gastrin production (4)

Answer 13

1. antral ditension (full)
2. AAs
3. vagal stim - see food
4. rising pH

Question 14

what stims histamine release (2)

Answer 14

1. gastrin

2. vagal nerve

Question 15

how is acid secretion inhibited in stomach?

Answer 15

1. low pH
2. stims D cell to release somatostatin
3. somatostatin is inhib to G cells
4. gastrin lowered

Question 16

how is acid secretion inhibited by duodenum?

Answer 16

enterogastric reflex

1. food in duodenum
2. secretin and CCK released from duod.
3. CCK stims somatostain and inhib gastrin
4. secretin inhibs gastrin and parietal cells directly

Question 17

3 places gastric acid signalling comes from

Answer 17

1. cephalic (20%
2. gastric 70%
3. duodenum 10%

Question 18

what is mucosal barrier

Answer 18

1. mucus by mucous cels stimulated by food contents

2. epithelium secretes alkaline fluid in and stuck inmucous to protect stomach lining

Question 19

function of gastric pepsin

Answer 19

primary protease

Question 20

what stims gastric pepsin

Answer 20

ACH along with acid

Question 21

what does chief cell secrete

Answer 21

pepsinogen - cleaved to pepsin by acid

Question 22

function of intrinsic factor

Answer 22

binding of B12 for absorbtion

Question 23

function of gastric lipase

Answer 23

hydrolysis of triglycerides

Question 24

what is absorbed in stomach

Answer 24

very little - alcohol and ASA