GIT Functions (ppt) - Dr. Nobleza

Question 1

Largest portion of the stomach:

Answer 1

Body or corpus

Question 2

Most anterior part of the stomach:

Answer 2

Fundus

Question 3

The muscles of the stomach are arranged in such a way for ________ and _________.

Answer 3

Churning

Peristaltic motion

Question 4

Consists of a simple columnar epithelium that produces an alkaline carpet of mucus that covers the interior surfaces of the stomach and protects epithelial cells against the acid and enzymes in the gastric lumen.

Answer 4

Mucosa

• Lamina propria
• Muscularis mucosae

Question 5

Structures under muscularis externa:

Answer 5

Oblique muscle
Circular muscle
Longitudinal muscle

Question 6

The ______ allow the stomach to have a larger surface area.

Answer 6

Folds

Question 7

Secretions of the stomach secrete ______.

Answer 7

2 L/day

*Isotonic with plasma

Question 8

Made up of basal secretionL

Answer 8

Sodium rich (non-parietal cells)

Question 9

Stimulated secretion:

Answer 9

H+ rich (Parietal cells)

Question 10

Acid secretion
Pepsinogen
Intrinsic factor

Answer 10

Corpus

Question 11

Acid

IF

Answer 11

Parietal cells or oxyntic cells

Question 12

Secrete pepsinogen not acid

Answer 12

Chief or peptic cells

Question 13

If chief or peptic cells reach pH <3 activated to:

Answer 13

Pepsins

Question 14

Mucus secreting cells

Answer 14

Chief or peptic cells

Question 15

Endocrine cells

Answer 15

Chief or peptic cells

Question 16

No parietal cells and no acid secretion

Answer 16

Antrum

Question 17

G cells produce:

Answer 17

Gastrin

• Gastric acid secretion
• Trophic effect

Question 18

D cells produce:

Answer 18

Somatostatin

Question 19

Inhibit gastrin release and parietal acid secretion

Answer 19

Somatostatin

Question 20

______ are present throughout the fundus and body, branched, tubular gastric glands.

Answer 20

Glands

• Mucous neck cells
• Chief cells
• Parietal cells
• Stem cells
• Enteroendocrine cells

Question 21

Secretes mucus

Answer 21

Surface mucous cell and mucous neck cell

Question 22

Secretes hydrochloric acid and intrinsic factor

Answer 22

Parietal cell

Question 23

Secretes pepsinogen and gastric lipase

Answer 23

Chief cell

Question 24

Secretes the hormone gastrin

Answer 24

G cell

Question 25

Also secretes bicarbonate and protects the lining.

Answer 25

Mucous neck cell

Question 26

Large triangular cell, inc mitochondria, intracellular tubulovesicular membrances

Answer 26

Parietal cell

Question 27

Secretes mucus

Answer 27

Surface mucus cells

Question 28

Secretes mucus and pepsinogen

Answer 28

Mucus neck cells

Question 29

Secrete pepsinogen

Answer 29

Peptic or chief cells

Question 30

Secrete HCl intrinsic factor

Answer 30

Oxyntic or parietal cell

Question 31

Secretes hormones

Answer 31

Endocrine

Question 32

Enterochromaffin like cells:

Answer 32

Histamine

Question 33

In BASAL state, the rate of acid secretion is _____.

Answer 33

Low

Question 34

Tubolovesicular membrane present in resting nonstimulated parietal cell has __________

Answer 34

H-K pump

Question 35

Responsible for acid secretion

Answer 35

Pump

Question 36

In basal state, luminal pH of stomach is ______ and the rate of acid secretion is _____.

Answer 36

4-6 | Low

Question 37

With stimulation the pH of gastric secretion is ______

Answer 37

<2

Question 38

Ach, Gastrin, Histamine _______ stimulate acid secretion by acting on different receptors.

Answer 38

Directly

Question 39

Ach and gastrin also _____ stimulate by actin on ECL cell.

Answer 39

Indirectly

Question 40

Large polypeptide

Answer 40

Gastrin

Question 41

More active | Antral G cells

Answer 41

G-17

Question 42

Slower degradation | Duodenal G-cells

Answer 42

G-34

Question 43

Stimulation of acid secretion by parietal cells

Answer 43

Gastrin

Question 44

Release of histamine by ECL cells

Answer 44

Gastrin

Question 45

Regulation of mucosal growth (trophic effect) on corpus | SI and LI

Answer 45

Gastrin

Question 46

Polypeptide hormone

Answer 46

Somatostatin

Question 47

D cells corpus (endocrine) is triggered by _____ and ______ mechanism

Answer 47

Neural | Hormonal

Question 48

D cells antrum (paracrine) is stimulated by ____ intraluminal pH

Answer 48

Low

Question 49

Delta cells of pancreas and hypothalamus

Answer 49

Somatostatin

Question 50

GI predominant form in somatostatin

Answer 50

SS-28

Question 51

SS-14

Answer 51

Somatostatin

Question 52

Inhibits gastric acid secretion

Answer 52

Somatostatin

Question 53

Fat, acid and hyperosmolar solution

Answer 53

Enteric hormones

Question 54

Potent inhibitor of gastric acid secretion

Answer 54

Enteric hormones

Question 55

Most potent inhibitor

Answer 55

Lipid

Question 56

S cells duodenum

Answer 56

Secretin

Question 57

Inhibition of release of gastrin from antrum

Answer 57

Secretin

Question 58

Stimulation of somatostatin release

Answer 58

Secretin

Question 59

Direct down regulation of parietal H release

Answer 59

Secretin

Question 60

Triggered by low pH because too much acid may cause duodenal ulcers.

Answer 60

S cells

Question 61

Stomach can handle an acidic environment because of its:

Answer 61

Gastric diffusion barrier

Question 62

Gastric diffusion barrier is composed of:

Answer 62

1. Apical membrane and epithelial tight junctions 2. Bicarbonate layer (produces bicarbonate) 3. Mucuous layer (20-50 micro meter)

Question 63

How come Gastric Acid is still produced by cells that are being covered?

Answer 63

Viscous fingering

Question 64

From the time that your HCl acid is released, it passes through 3 barriers (______, _______ and _______) in a straight finger like fashion, eventually extruded out.

Answer 64

apical bicarbonate mucous

Question 65

Gastric inhibitory peptide (GIP) DIRECTLY inhibits:

Answer 65

Parietal cell acid secretion

Question 66

GIP INDIRECTLY inhibits:

Answer 66

Antral gastrin release

Question 67

I cells in duodenum/jejenum release:

Answer 67

CCK - Cholecytoskinin

Question 68

The feedback inhibition directly reduces gastric acid secretion by parietal cells

Answer 68

CCK

Question 69

Inhibits histamine activation

Answer 69

Prostaglandins (PGE2)

Question 70

Common ingredients in the action of enteric hormones

Answer 70

G-alpha

Question 71

Acts on IP3 directly, then calcium or through adenylyl cyclase

Answer 71

G-alpha

Question 72

Can stimulate or not stimulate the secretion of hormones, depending on the increase or decrease of adenylyl cyclase or calcium

Answer 72

G-aplha

Question 73

What can trigger acid secretion?

Answer 73

* Taking medicines like NSAIDS * Stress (neural stimulation can increase acid secretion) * Alcohol intake * H. pylori infection

Question 74

Initiate hydrolysis of ingested proteins in the stomach

Answer 74

Pepsins

Question 75

Secreted from base of glands in corpus of stomach

Answer 75

Group 1 pepsinogen

Question 76

Chief cells and mucus neck cells of cardia, corpus and antral areas

Answer 76

Group 2 pepsinogens

Question 77

Basal secretion of pepsinogen is _____ of maximal secretion after stimulation.

Answer 77

20%

Question 78

Fusion of secretory granules with plasma membrane and other secretory granules

Answer 78

Compound exocytosis

Question 79

Emptying of liquids

Answer 79

Smooth muscle (Proximal part)

Question 80

Emptying of solids

Answer 80

Antral smooth muscles