SLP 1 GIT

Question 1

Explain how glucose molecules is absorbed across intestinal epithelium.

Answer 1

Glucose enters the cell through the apical membrane by co-transport with Na+ and
leaves the cell through the basal membrane by facilitated diffusion

Question 1

The function of the gastrointestinal (GI) tract can be summarized by

Answer 1

Motility
Secretion
Digestion
Absorption

Question 2

Most of the chemical digestion in the gastrointestinal (GI) tract occurs in the

Answer 2

Small intestina

Question 3

Most of the water and electrolytes absorbed across the walls of the gastrointestinal (GI) tract
is absorbed in t

Answer 3

large intestine

Question 4

Fat digestion begins in this region of the gastrointestinal (GI) tract.

Answer 4

mouth

Question 5

) After fat molecules are eventually placed into micelles in the lumen of the gastrointestinal (GI)
tract, they are digested by pancreatic lipase to form

Answer 5

free fatty acids, monoglycerides

Question 6

The chemical digestion of this class of compounds begins in the small intestine

Answer 6

nucleic acids

Question 7

describe enteric nervous system

Answer 7

(A) It is capable of responding independently to stimuli within the gastrointestinal tract.
(B) Its function is regulated by the autonomic nervous system.
(C) It is sometimes referred to as the “little brain”.
(D) It uses serotonin as its main neurotransmitter.

Question 8

In the stomach, hydrochloric acid (HCl) is secreted by

Answer 8

parietal cell

Question 9

enzymes secreted by the pancreas into the duodenal region of the small
intestine

Answer 9

(A) Bicarbonate
(B) Amylase
(C) Nuclease
(D) Peptidase

Question 10

A. Small intestine mucosa secrete ….. liter of aqueous salt & mucus solution from duodenal
submucosal called……….

Answer 10

1) 1.5 litre - 2 litre
2)intestinal juice

Question 11

Aqueous salt composed of …..,……,……,……. Its function is to…….. , ………….and the
Secretion is increased by the presence of …………..

Answer 11

1) potassium, chloride, water, sodium, bicarbonate
2)neutralize stomach acid
3)provide appropriate pH for enzyme to be activated
4) hormonal signals, neural inputs, dietary factors

Question 12

The absorbed forms of proteins are

Answer 12

amino acids, dipeptides, tripeptides

Question 13

trypsin and chymotrypsin split proteins into…

Answer 13

oligopeptides and amino acids

Question 14

Carboxypeptidase splits….. from ……. of proteins

Answer 14

1) single amino acids
2)carboxyl end

Question 15

. The brush border enzymes: ………. and …… continue the digestion of peptides

Answer 15

1)aminopeptidase
2)dipeptidase

Question 16

G. Bile salts molecules are amphipathic which means one side is ………………., and
…………… on the other.

Answer 16

1) hydrophilic (water loving)
2)polar

Question 17

. Vitamin K is a product necessary for blood clotting activity and is produced by

Answer 17

It is produced by the bacteria that live in the large intestine

Question 18

. The differentiate role of cholecystokinin (CCK) in regulating bile secretion at gall
bladder and Sphincter of Oddi is

Answer 18

Contraction of gall bladder; relaxation of Sphincter of Oddi

Question 19

enzymes that inhibits intestinal motility

Answer 19

secretin

Question 20

the best place for absorption of vit B12

Answer 20

ileum

Question 21

Accelerates gastric emptying, stimulates intestinal peristalsis and stimulates
the production of pepsin

Answer 21

gastrin

Question 22

Stimulate the mucus secretions of Brunner’s glands.

Answer 22

secretin

Question 23

Hormonal control for relaxation of ileoceccal sphincter.

Answer 23

gastrin

Question 24

function of saliva

Answer 24

-moisturising and lubricating
-digestion
-taste
-protection
-antibacterial

Question 25

Describe briefly the peristalsis process at the esophageal phase.

Answer 25

During the esophageal phase of peristalsis, the bolus of food enters the esophagus after swallowing. This triggers a reflexive response in the esophageal muscles, causing a wave-like contraction known as peristalsis. The circular muscles behind the bolus contract while the muscles ahead of it relax, propelling the food downward toward the stomach. This coordinated muscular movement ensures that the food travels in the correct direction, despite being inverted in the esophagus. Once the food reaches the lower esophageal sphincter, it relaxes to allow passage into the stomach, where further digestion occurs.

Question 26

Distinguish between the THREE (3) motor functions of the stomach.

Answer 26

-storage of large quantities of food
-preparing chyme for digestion in small intestine
-absorption of water and lipid soluble substances
-slow emptying of chyme from the stomach into the small intestine.

Question 27

describe cephalic and gastric phase which helps regulates gastric secretion.

Answer 27

Cephalic Phase:
The cephalic phase of gastric secretion occurs before food enters the stomach, primarily in response to sensory stimuli such as sight, smell, taste, and even the thought of food. These stimuli activate the vagus nerve, which sends signals to the stomach’s parietal cells to start secreting gastric juices. This phase prepares the stomach for the arrival of food by increasing gastric blood flow, gastric motility, and the secretion of hydrochloric acid and pepsinogen, which aid in digestion.

Gastric Phase:
The gastric phase of gastric secretion begins when food enters the stomach. Distension of the stomach wall and the presence of proteins and peptides in the stomach lumen trigger the release of gastrin hormone from the G cells in the gastric glands. Gastrin stimulates the parietal cells to secrete hydrochloric acid and the chief cells to secrete pepsinogen. This phase further enhances gastric motility and secretion, ensuring the proper breakdown of food components for digestion and absorption in the small intestine.