Epithelial Cells Are Continually Being Shed from the Villi Because

question 296

Multiple Choice

Epithelial cells are continually being shed from the villi because

• A) the intracellular enzymes digest important cellular constituents, causing the cells to disintegrate and slough.
• B) the body needs a continual supply of protein derived from the digestion of these cells.
• C) new cells are continually being produced in the crypts at the base of the villi and migrate upward.
• D) acid entering the small intestine from the stomach constantly destroys the small intestinal lining, causing the cells to slough.
• E) none of these answers.

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Definitions:

Bicarbonate Ions

An alkaline ion that acts as a pH buffer in blood and other bodily fluids.

Red Blood Cell Membrane

The semi-permeable membrane that encloses the cytoplasm of red blood cells, maintaining its shape and flexibility, and facilitating gas exchange.

Alveolar Pressure

The pressure within the lung alveoli, which changes during different phases of breathing.

Inspiration

The process of drawing air into the lungs, an essential component of breathing and gas exchange in the respiratory system.