SLP 1 GIT Flashcards
Explain how glucose molecules is absorbed across intestinal epithelium.
Glucose enters the cell through the apical membrane by co-transport with Na+ and
leaves the cell through the basal membrane by facilitated diffusion
The function of the gastrointestinal (GI) tract can be summarized by
Motility
Secretion
Digestion
Absorption
Most of the chemical digestion in the gastrointestinal (GI) tract occurs in the
Small intestina
Most of the water and electrolytes absorbed across the walls of the gastrointestinal (GI) tract
is absorbed in t
large intestine
Fat digestion begins in this region of the gastrointestinal (GI) tract.
mouth
) After fat molecules are eventually placed into micelles in the lumen of the gastrointestinal (GI)
tract, they are digested by pancreatic lipase to form
free fatty acids, monoglycerides
The chemical digestion of this class of compounds begins in the small intestine
nucleic acids
describe enteric nervous system
(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.
In the stomach, hydrochloric acid (HCl) is secreted by
parietal cell
enzymes secreted by the pancreas into the duodenal region of the small
intestine
(A) Bicarbonate
(B) Amylase
(C) Nuclease
(D) Peptidase
A. Small intestine mucosa secrete ….. liter of aqueous salt & mucus solution from duodenal
submucosal called……….
1) 1.5 litre - 2 litre
2)intestinal juice
Aqueous salt composed of …..,……,……,……. Its function is to…….. , ………….and the
Secretion is increased by the presence of …………..
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
The absorbed forms of proteins are
amino acids, dipeptides, tripeptides
trypsin and chymotrypsin split proteins into…
oligopeptides and amino acids
Carboxypeptidase splits….. from ……. of proteins
1) single amino acids
2)carboxyl end
. The brush border enzymes: ………. and …… continue the digestion of peptides
1)aminopeptidase
2)dipeptidase
G. Bile salts molecules are amphipathic which means one side is ………………., and
…………… on the other.
1) hydrophilic (water loving)
2)polar
. Vitamin K is a product necessary for blood clotting activity and is produced by
It is produced by the bacteria that live in the large intestine
. The differentiate role of cholecystokinin (CCK) in regulating bile secretion at gall
bladder and Sphincter of Oddi is
Contraction of gall bladder; relaxation of Sphincter of Oddi
enzymes that inhibits intestinal motility
secretin
the best place for absorption of vit B12
ileum
Accelerates gastric emptying, stimulates intestinal peristalsis and stimulates
the production of pepsin
gastrin
Stimulate the mucus secretions of Brunner’s glands.
secretin
Hormonal control for relaxation of ileoceccal sphincter.
gastrin
function of saliva
-moisturising and lubricating
-digestion
-taste
-protection
-antibacterial
Describe briefly the peristalsis process at the esophageal phase.
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.
Distinguish between the THREE (3) motor functions of the stomach.
-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.
describe cephalic and gastric phase which helps regulates gastric secretion.
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.
