The 'Hormone Peptide YY' (PYY) is secreted by the L cells of the distal gastrointestinal tract (ileum and colon) in response to food intake. Its primary function is to: MCQ with Answer and Explanation

The 'Hormone Peptide YY' (PYY) is secreted by the L cells of the distal gastrointestinal tract (ileum and colon) in response to food intake. Its primary function is to:
A. Inhibit gastric emptying and pancreatic secretion, and reduce appetite (satiety signal)
B. Stimulate gastric acid secretion
C. Stimulate appetite
D. Increase intestinal motility
Answer: Option A
Solution (By JKExamLibrary)
Peptide YY (PYY) is a gut hormone secreted by the L cells in the mucosa of the distal small intestine (ileum) and colon, primarily in response to food ingestion, especially fats. Its primary functions are related to the 'ileal brake' mechanism: it inhibits gastric emptying and pancreatic exocrine secretion, slowing down the transit of food through the upper GI tract to allow more time for digestion and absorption in the ileum. It also acts on the hypothalamus to reduce appetite, serving as a satiety signal.

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