The small intestine is specialized for absorption. The absorptive effectiveness is enhanced by increasing the surface area of the intestinal wall. Which of the following accomplish this task?
A) plicae circulares and intestinal villi
B) digestive enzymes
C) intestinal glands
D) the rugae

Question

Quizplus · Accepted Answer

The plicae circulares are circular folds of the intestinal mucosa that increase the surface area available for absorption. The intestinal villi are finger-like projections of the mucosa that further increase the surface area. Digestive enzymes break down nutrients so they can be absorbed, but they do not increase surface area. Intestinal glands secrete mucus and other substances, but they do not increase surface area. The rugae are folds in the stomach mucosa that allow for expansion, but they are not part of the small intestine.

The Small Intestine Is Specialized for Absorption