Question

Muscular contractions called _________ involve alternating ring-like constrictions at several places along the intestine.

Options:
A) Peristalsis
B) Segmentation
C) Pendular movements
D) Haustral churning

Answer 1

Segmentation refers to the muscular contractions featuring ring-like constrictions that mix intestinal contents, primarily in the small intestine.

Step-by-step explanation:

The muscular contractions that involve alternating ring-like constrictions at several places along the intestine are known as segmentation. These localized contractions of the circular muscle in the muscularis layer of the alimentary canal occur mainly in the small intestine. Segmentation's primary function is to mix food with digestive juices and facilitate the absorption of nutrients by moving the contents back and forth in the intestinal lumen. Unlike peristalsis, which is responsible for moving food through the digestive tract with alternating waves of contraction and relaxation, segmentation isolates small sections of the intestine to thoroughly mix and aid in the digestive process.