Question

The bacterium Vibrio cholerae causes the disease cholera. Infected people have such severe diarrhea, that they may lose as much as 20 L of fluid in a 24 hour period. The bacterium enters the body when a person drinks contaminated water, then attaches to the intestinal lining. During its metabolic activities, it secretes a compound that is toxic to cells of the lining, and they start secreting chloride ions. Sodium ions follow the chloride ions into the fluid in the intestines. Explain how this sequence of events causes the massive fluid losses.

Answer 1

Cholera is caused by the bacterium Vibrio cholerae and leads to severe fluid loss through profuse diarrhea. The increase in cyclic AMP levels in intestinal cells due to the toxin released by the bacterium activates a chloride channel, causing the release of chloride ions into the intestinal lumen. Water follows the movement of ions, resulting in massive fluid losses.

Step-by-step explanation:

Cholera and Fluid Loss

Cholera is caused by the bacterium Vibrio cholerae, which attaches to the intestinal lining and releases a toxin. This toxin causes an increase in cyclic AMP levels in the intestinal cells, activating a chloride channel and leading to the release of chloride ions into the intestinal lumen. Because water follows the movement of ions, the increased osmotic pressure in the lumen causes water to enter the intestines, resulting in profuse diarrhea and fluid loss.