Lecture 3 - Part 1 MC Flashcards
How does acetylcholine contribute to stomach digestion?
A) It decreases acid secretion in the stomach.
B) It is released by the sympathetic nervous system.
C) It increases acid secretion through signals sent via the vagus nerve.
D) It acts directly on the stomach to decrease enzyme activity.
Correct Answer: C
What is the role of histamine in the stomach?
A) It decreases the release of gastric juices.
B) It acts locally through H2-receptors on nearby cells to release HCl.
C) It inhibits the release of gastrin.
D) It is released by the sympathetic nervous system.
Correct Answer: B
Gastrin is released by which of the following and what does it stimulate?
A) Sympathetic nervous system cells; it stimulates pepsin release.
B) Enteroendocrine cells in the gastric pits of the pyloric region; it stimulates acid secretion.
C) Oxyntic cells; it stimulates bile release.
D) Adrenal gland; it stimulates adrenaline.
Correct Answer: B
What is the importance of the conversion from ferric to ferrous salts in the stomach?
A) It enhances the breakdown of heme iron.
B) It assists in the absorption of nonheme iron.
C) It helps in the digestion of plant fibers.
D) It reduces the effectiveness of stomach enzymes.
Correct Answer: B
What is the role of intrinsic factor produced by oxyntic cells in the stomach?
A) It enhances carbohydrate digestion.
B) It protects vitamin B12 from acidity and enzymatic destruction, aiding its absorption.
C) It stimulates bile release to emulsify fats.
D) It inhibits protein digestion to slow down enzyme wear.
Correct Answer: B
Which phase of gastric secretion is primarily triggered by the smell, taste, or thought of food?
A) Cephalic phase
B) Gastric phase
C) Intestinal phase
D) Pyloric phase
Correct Answer: A
What percentage of acid secretion occurs during the gastric phase?
A) 10%
B) 30%
C) 60%
D) 90%
Correct Answer: C
Which factor does NOT trigger the intestinal phase of gastric secretion?
A) Stomach distension
B) Distention of the small intestine
C) Presence of proteins in the small intestine
D) Products of protein digestion
Correct Answer: A