During urine production, what happens if the water content of the blood is too low?
a. membrane channels are produced in the cells of the collecting duct.
b. the pituitary gland stops secreting adh.
c. the collecting duct becomes less permeable to water.
d. large volumes of dilute urine are formed.

The answer is: A. Membrane channels are produced in the cells of the collecting duct.

the answer describes the function of ADH.

The other answers are wrong because:
The pituitary gland increases secretion of ADH. ADH is anti-diuretic hormone, which allows your body to hold on to water. diuresis means urine excretion by the kidney. So ADH decreases that.

The collecting duct (in the kidney) becomes more permeable to water (this is how ADH works).

Smaller volumes of concentrated urine are formed (in order to preserve water in the body).

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