University of Central Florida (UCF) PCB3703C Human Physiology Exam 4 Practice

The small intestine is the primary site for potassium absorption in the gastrointestinal tract. This absorption occurs through both active and passive transport mechanisms, primarily in the jejunum and ileum. The cells lining the small intestine have specialized transporters that facilitate the movement of potassium ions from the intestinal lumen into the bloodstream.

Although potassium is present throughout the gastrointestinal tract, and some absorption occurs in other areas like the large intestine, the majority of potassium that the body absorbs comes from the content processed in the small intestine. This is particularly vital since potassium plays a crucial role in various physiological functions, including nerve transmission, muscle contraction, and maintaining fluid balance in the body.

Potassium absorption is influenced by dietary intake, renal function, and overall gastrointestinal health, which also underscores the importance of the small intestine in efficiently absorbing this essential nutrient.