The Hormone That Regulates Water Reabsorption by the Kidneys

Question

The hormone that regulates water reabsorption by the kidneys
A) decreases water permeability throughout the kidney tubules.
B) increases water permeability throughout the kidney tubules.
C) only decreases water permeability in certain portions of the kidney tubules.
D) only increases water permeability in certain portions of the kidney tubules.

Accepted Answer

The hormone referred to is antidiuretic hormone (ADH), also known as vasopressin. It specifically increases water permeability in the collecting ducts and distal convoluted tubule of the kidney, allowing the body to reabsorb water and thus concentrate the urine. This action does not affect the entire kidney tubule uniformly, hence the correct answer is that it only increases water permeability in certain portions of the kidney tubules.