Question

Which cells of 'Crypts of Lieberkuhn' secrete antibacterial lysozyme?
A. Kupffer cells
B. Argentaffin cells
C. Paneth cells
D. Zymogen cells

Answer 1

They are located in the intestine next to the stem cells. The cells form dense granules where an abundance of antimicrobial peptides and immunomodulating proteins function to control the composition of the intestinal region.

Complete answer:
The mucosa is the innermost layer of the lumen of the alimentary canal that forms irregular folds in the stomach and thin finger-like folds called villi in the small intestine. The cells lining the villi form numerous microscopic structures known as microvilli. Mucosal epithelium contains goblet cells that secrete mucus that help in lubrication. The mucosa also gives rise to glands in the stomach and crypts between villi in the intestine called crypts of Lieberkuhn.

Kupffer cells are located in the liver and play a crucial role in sustaining liver function. Zymogen cells are secreted from the chief cells of the digestive glands.
Argentaffin cell is a circular or slightly flattened cell located in the crypts and contains granules considered to be secretive. Their granules contain a chemical called serotonin that induces smooth muscle contractions.
The crypts have Paneth cells at the bottom of the crypts. Paneth cells are activated to secrete defenses when exposed to bacteria or bacterial products. They also secrete lysozyme which has strong antimicrobial activity.

Thus, the correct answer is option c i.e., Paneth cells.

Note: These contain several cells, such as stem cells, which produce new cells to replace the old worn out cells, as well as enteroendocrine cells to synthesise and secrete hormones. The enteroendocrine cells secrete hormones in against a number of stimuli.