Question

Which of the following cells of the intestine secretes GIP?
A. I cell
B. K cell
C. Beta cell
D. None of the above

Answer 1

Gastric inhibitory polypeptide, also known as glucose-dependent insulinotropic polypeptide, is an inhibitory hormone that belongs to the secretin family of hormones. Its primary function is to promote insulin secretion, despite the fact that it is a poor inhibitor of stomach acid secretion.
GIP, along with glucagon-like peptide-$1$, is a member of the incretin family of chemicals.
It was discovered to decrease the secretion of stomach acid to protect the small intestine from acid damage, reduce the rate at which food is transferred through the stomach, and inhibit GI motility and acid secretion. It was previously known as gastrointestinal inhibitory peptide or gastric inhibitory peptide.

Complete answer:
Option A: I cells are found in the duodenum and jejunum and release cholecystokinin (CCK). Bile secretion, exocrine pancreas secretion, and satiety are all influenced by them.
So, option A is not correct.
Option B: GIP is an amino-acid peptide released by enteroendocrine K cells in the duodenum and proximal jejunum. GIP levels rise shortly after a nutrient is consumed, inhibiting stomach acid output and gastrointestinal motility to a minor extent.
So, option B is correct.
Option C: Beta cells produce insulin, a hormone that regulates the amount of glucose (a form of sugar) in the bloodstream. In the pancreas, beta cells are found in islets, which are clusters of cells. The immune system incorrectly damages the beta cells in type $1$ diabetes.
So, option C is not correct.
Option D: GIP (gastric inhibitory polypeptide) or gastric inhibitory peptide, also known as glucose-dependent insulinotropic peptide, is a secretin-family suppressing hormone.
K cells, which can be located in the mucosa of the duodenum and the jejunum of the gastrointestinal tract, produce it. As a result, the intestine's K cell secretes GIP.
So, option D is not correct.

Therefore, Option B is the correct answer.

Note:
The small intestine contains an enteroendocrine cell that produces gastric inhibitory peptide (glucose-dependent insulinotropic peptide). This peptide causes the pancreas' beta cells to release insulin.
K cells are an enteroendocrine cell subpopulation found mostly in the stomach, duodenum, and jejunum. They emit glucose-dependent insulinotropic peptide (GIP) in a glucose-dependent way, which stimulates the fast release of insulin from pancreatic -cells after a meal.