Which histological feature of the small intestine is correctly matched to its product

Which histological feature of the small intestine is correctly matched to its product? Duodenal glands: acidic mucus Paneth cells: lysozyme S cells: CCK K cells: secretin Goblet cells: intestinal juice

The correct answer and explanation is:

The correct match is: Paneth cells: lysozyme

Explanation:

The small intestine has specialized histological features, each associated with particular secretory products that aid digestion and protect the mucosa.

1. Duodenal glands (Brunner’s glands):
   These glands are located in the submucosa of the duodenum. Their primary secretion is alkaline mucus, not acidic mucus. This mucus contains bicarbonate ions, which help neutralize the acidic chyme coming from the stomach to protect the intestinal lining and provide an optimal pH for enzymatic activity.
2. Paneth cells:
   Found at the base of the crypts of Lieberkühn in the small intestine, especially in the ileum. Paneth cells secrete lysozyme, an enzyme that breaks down bacterial cell walls and helps maintain intestinal flora balance by providing an antimicrobial defense. They also secrete other antimicrobial peptides, including defensins.
3. S cells:
   These enteroendocrine cells are located mainly in the duodenum and jejunum and secrete secretin, a hormone that stimulates the pancreas to release bicarbonate-rich pancreatic juice and inhibits gastric acid secretion. They do not secrete cholecystokinin (CCK).
4. K cells:
   Also enteroendocrine cells, K cells secrete glucose-dependent insulinotropic peptide (GIP), which stimulates insulin release from the pancreas in response to glucose in the intestinal lumen. They do not secrete secretin.
5. Goblet cells:
   These cells produce mucus, which lubricates and protects the intestinal mucosa. They do not produce “intestinal juice” as a whole; intestinal juice is a mixture of secretions from various cells, including absorptive cells and glands.

Summary Table:

Why is this important?

Understanding the histological features and their secretions is crucial in physiology and pathology, as these secretions regulate digestion, absorption, and mucosal defense. Misidentification can lead to confusion when studying gastrointestinal diseases or interpreting histology slides in medical fields.