Antidiuretic hormone causes the kidneys to
a. produce a larger volume of very dilute urine.
b. increases the permeability of the collecting ducts to water.
c. release is insensitive to the osmolarity of interstitial fluid.
d. is secreted in response to low potassium ion in the blood.
e. is secreted by the anterior pituitary.

Anti-diuretic hormone causes the kidneys to increases the permeability of the collecting ducts to water .

Explanation:

The anti-diuretic hormones stimulates the process of water re-absorption by enhancing the water channels or aquaporins in the membranes of the kidney tubules. The solute free water are transferred through the channels in the tubular cells and back in the blood which then leads to decrease in the osmolarity of plasma with the increase in osmolarity of urine. The hormone is prepared in the hypothalamus of brain and stored in the pituitary glands. It reminds the kidney about the absorption of water, through which it maintains the balance of water in blood.

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