GIT quiz questions Flashcards
what does not directly enter the blood upon being absorbed from the digestive tract?
monoglycerides and free fatty acids
What stimulates gallbladder contraction?
Cholecystokinin (CCK)
What does not enter the duodenal lumen?
Disaccharidases
The primary factor responsible for moving the chyme forward in the S.I is?
A gradient in the frequency of segmentation along the length of the S.I
The gastroesophageal sphincter is normally closed to prevent:
gastric contents from refluxing into the esophagus
Correct stament about the colon
The colon contains about 10-fold more bacteria than the body has cells
What is absorbed by receptor-mediated endocytosis in the terminal?
Vitamin B12
Venous flow from the digestive tract into the liver is via the:
Hepatic portal vein
As food leaves the stomach, gastric secretion is reduced. Which of the following factors does NOT contribute to this reduction?
Beginning the next meal
Correct statement concerning HCI secretion by the stomach
(All) HCI kills microorganisms, HCI activates pepsinogen, HCI establishes a low pH in the stomach
Stimulation of saliva secretion by the conditioned reflex originates in:
Cerebral cortex
How does the topical agent pilocarpine increase salivation?
By acting on muscarinic receptors
If a person has dysphagia affecting the pharyngeal phase of swallowing, it is likely that:
The larynx does not elevate adequately
Reflux is caused by stomach contents entering the oesophagus. This can occur due to:
(All) Loss of tone to the lower oesophageal sphincter, decreased pressure in the oesophagus during breathing, An increase in intra-abdominal pressure
How does H. Pylori infection contribute to peptic ulcer formation?
Disrupting tight junctions
Biliary obstruction leads to jaundice by preventing removal of the waste product bilirubin. The most common cause of obstruction is:
Choleliths (gall stones)
In Celiac disease there is blunting of microvilli. The following consequences would NOT impact digestion or absorption of nutrients:
Constipation
Ulcerative colitis is characterised by chronic inflammation in the colon leading to diarrhoea. Diarrhoea is a function of:
Loss of control of fluid flux
what are the 4 main layers of the GI tract?
mucosa, submucosa, muscularis externa, serosa
