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Flashcards in GIT Deck (33):
0

What hormone is stimulated by fat in small intestine?

Cholecystokinin

1

What cells produce cholecystokinin ?

Gut endocrine cells (I cells) of the mucosa of the small intestine

2

In the stomach what release pepsinogen?

Chief cells

3

What activates pepsinogen?

1. Acidic pH
2. Pepsin

4

What is pepsinogen?

An inactive pre cursor of the proteolytic enzyme pepsin

5

The breakdown of complex food stuff is accomplished by?

Hydrolysis

6

Complex starches are mainly digested by enzymes secreted from?

Pancreas (alpha amylase)

7

Which process transports AA across the luminal surface of the epithelium that lines the small intestine?

Co transport with NA ion

8

How does the stomach not digest itself?

1. Gastric mucosal cells transport H ions out of gastric mucosa
2. Pepsin is stored as pepsinogen so it will only be released when needed and does not digest the bodies own protein in stomach lining

9

How is stored fat usually transported from 1 side of the body to the other?

Free fatty acids

10

What is the concentration of free fatty acids in plasma?

15mg/dl

11

What is an essential AA?

An amino acid that cannot be synthesised de novo and must therefore be supplied by the diet

12

What are the 9 essential AA?

1. Histidine
2. Isoleucine
3. Lysine
4. Leucine
5. methionine
6. Phenylalanine
7. Threonine
8. Tryptophan
9. Valine

13

What are the conditionally essential amino acids?

1. Arginine
2. Cystine
3. Glycine
4. Tyrosine

14

What is the meaning of a conditionally essential amino acid?

Not normally require in the diet but must be supplied exogenously to specific populations that do not synthesise adequate amounts

15

What hormones are secreted by the duodenum?

1. Secretin

16

What does secretin do?

1.Regulates water homeostasis throughout the body
2. Helps regulate the ph of the duodenum by inhibiting the secretion of gastric acid from the parietal cells of the stomach; and
3. stimulating the production of bicarbonate from the centroacinar cells and intercalated ducts of the pancreas

17

Which cells secrete intrinsic factor?

Parietal cells

18

Where are kupffer cells found?

Liver
Have phagocytic properties

19

What do parietal cells secrete ?

1. HCL
2. Ca
3. Na
4. Mg
5. IF

20

Cephalic phase

30% of acid production
Vagal cholinergic stimulation causing secretion of HCL and gastrin release from G cells

21

Gastric phase

60% of acid produced
Stomach distension

22

Intestinal phase

10% of acid production

23

Factors increasing gastric acid production

1. Vagal nerve stimulation
2. Gastrin release
3. Histamine release (indirectly following gastrin release) from enterochromaffin cells

24

Factors decreasing gastric acid production

1. Somatostatin (inhibits histamine release)
2. Cholecystokinin
3. Secretin

25

What cells secrete secretin ?

S cells of duodenum - located in the crypts of lieberkuhn

26

What goes gastrin do?

1. Increase HCL
2. Increase pepsinogen
3. Increase IF
4. Increase gastric motility
5. Trophic effect on gastric mucosa

27

What cells secrete gastrin?

G cells in Antrum of the stomach

28

What cells secrete CCK?

I cells in upper small intestine

29

What does CCK do?

1. Increase secretion of enzyme rich fluid from the pancreas
2. Contraction of the gallbladder and relaxation of sphincter oddi
3. Decrease gastric emptying
4. Trophic effect on pancreatic acinar cells
5. Induces satiety

30

What does VIP do?

1. Stimulates secretion by pancreas and intestines
2. Inhibits acid and pepsinogen secretion

31

What does somatostatin do?

1. Decreases acid and pepsin secretion
2. Decreases gastrin secretion
3. Decreases pancreatic enzyme secretion
4. Decreases insulin and glucagon secretion
5. Inhibit strophic effect of gastrin
6. Stimulates gastric mucus production

32

Sympathetic innervation of abdomen

From thoracolumbar sympathetic outflow pass though sympathetic chain without synapsing and form greater(T5-9), lesser(T10-11) and least splanchnic nerves
The fibres from the greater and lesser splanchnic nerves synapse at the coeliac ganglion