Question

Vasopressin, or Antidiuretic hormone (ADH), is:

A. secreted into the blood from the posterior pituitary.
B. part of the filtrate.
C. secreted into the blood by the kidney.
D. secreted by the collecting duct.

Answer 1

ADH, also known as vasopressin, is secreted by the hypothalamus and acts on the kidneys to reabsorb more water and prevent fluid loss in urine. It helps increase fluid levels and restore blood volume and pressure.

Step-by-step explanation:

Antidiuretic hormone (ADH), also known as vasopressin, is secreted by the cells in the hypothalamus and transported via the hypothalamic-hypophyseal tracts to the posterior pituitary where it is stored until released upon nervous stimulation. The primary trigger prompting the hypothalamus to release ADH is increasing osmolarity of tissue fluid, usually in response to significant loss of blood volume. ADH signals its target cells in the kidneys to reabsorb more water, thus preventing the loss of additional fluid in the urine. This will increase overall fluid levels and help restore blood volume and pressure. In addition, ADH constricts peripheral vessels.