L5: Stomach

Question 1

LES (oesophagus) and cardia regions of stomach secrete which of the following:
H+
Intrinsic factor
Mucus
HCO3-
Pepsinogens
Lipase

Answer 1

HCO3-

Mucus

Question 2

Antrum and pylorus regions of stomach secrete which of the following:
H+
Intrinsic factor
Mucus
HCO3-
Pepsinogens
Lipase

Answer 2

H+
Intrinsic factor
Mucus
HCO3-
Pepsinogens
Lipase

Question 3

Fundus and body regions of stomach secrete which of the following:
H+
Intrinsic factor
Mucus
HCO3-
Pepsinogens
Lipase

Answer 3

Mucus

HCO3-

Question 4

Gastric motility takes place in which region of stomach?

Answer 4

Antrum

Question 5

Which type of signalling sensors via the vagus nerve is accommodation in the stomach dependent on?

Answer 5

Strecth signalling sensors

Question 6

What are the two roles of the duodenum in the control of gastric emptying?

Answer 6

1) Senses delivery of acid, amino acids, lipids

2) Secretes hormones

Question 7

What do chief (peptic) cells secrete?

Answer 7

Pepsinogen

Question 8

What type of hormone is gastrin?

Answer 8

Peptide hormone

Question 9

What type of cells release gastrin?

Answer 9

G cells

Question 10

What 2 forms of G cells are released?

Where are they mainly secreted from?

Answer 10

G17 - antrum of stomach

G34 - duodenum

Question 11

What is the role of CCK-PZ?

Answer 11

Causes release of digestive enzymes and bile –> suppresses hunger

Question 12

What stimulates gastrin release?

Answer 12

Lumeneal proteins/amino acids

Parasympathetic input

Question 13

What type of hormone is somatostatin?

Answer 13

Peptide hormone

Question 14

What are the 2 forms of amino acids in somatostatin?

Which of the two are mostly in the gut?

Answer 14

14 and 28

mostly in gut = 28aa

Question 15

What Is released from D cells?

Answer 15

Somatostatin - 14aa and 28aa

Question 16

What does somatostatin inhibit?

Answer 16

Release of gastrin

Question 17

Oxyntic/Parietal cells secrete what in response to histamine, acetylcholine and gastrin?

Answer 17

Acid (HCl) and intrinsic factor

Question 18

What is the name of the intrinsic factor secreted by parietal/oxyntic cells?
What does it bind to?

Answer 18

55 kDa glycoprotein

Cobalamin

Question 19

Where are endoproteases cut?

Answer 19

Within peptide chain (not at terminal end)

Question 20

What is the optimum pH of pepsin?

What pH denatures it?

Answer 20

2-3

Above 5-7

Question 21

What is the optimum pH of gastric lipase?

Answer 21

4

Question 22

What is the optimum pH of ptyalin a-amylase?

At what pH does it denature?

Answer 22

7

4

Question 23

Parietal/oxyntic cells secrete HCl and intrinsic factor in response to which 3 molecules?
How do the receptors of these moelcules respond?

Answer 23

Histamine - increase cAMP
Acetylcholine - increase intracellular Ca2+
Gastrin - increase intracellular Ca2+

Question 24

Which intrinsic factor is released by parietal cells into the stomach?

Answer 24

55 kDa glycoprotein

Question 25

Where does intrinsic factor bind to colbalamin (Vit B12)?

Answer 25

Small intestine

Question 26

Which part of the brain controls vomiting?

Answer 26

Area postrema

Question 27

Name 4 consequences of vomiting?

Answer 27

Salivation
Sweating
Hyperventilation
Retrograde peristalsis (loss of normal gut motility)