The main function of the small intestine is nutrient absorption. Which of the following structural qualities of the intestine in
crease absorption? Select all that apply. a. Very long tube almost 6 meters in length when relaxed
b. Internal wall covered with fingerlike projections called villi
c. Cell membrane of epithelial cells with multiple foldings
d. Higher pH than in the stomach, in part by secretion of bicarbonate
The food is digested and absorbed in the small intestine, a long folded tube which lengths about 20 ft or 6m.
The small intestine increases the surface area for food absorption as they have circular folding as well as the finger-like projections called villi and microvilli in the lumen of the intestine. These villi help in absorption of the nutrients from the intestine.
Facilitated diffusion pumps polar and charged molecules, such as carbohydrates, amino acids, nucleosides, and ions, cross the plasma membrane.
As sodium ion concentrations build outside the plasma membrane because of the action of the primary active transport process, an electrochemical gradient is created
