Final answer:
Diarrhea in diseases like cholera is due to problems in the function of the small intestine. Cholera is caused by the bacterium Vibrio cholerae, which produces a toxin that increases cyclic AMP (CAMP) levels within the intestinal cells.
Step-by-step explanation:
The diarrhea that is a symptom of diseases like cholera is due to problems in the function of the small intestine. Cholera is caused by the bacterium Vibrio cholerae, which produces a toxin that increases cyclic AMP (CAMP) levels within the intestinal cells. This leads to the activation of a chloride channel and the release of ions and water into the intestinal lumen, resulting in profuse diarrhea.