Diabetes insipidus (deficiency of antidiuretic hormone) causes a fall in the

A. True Due to failure of the kidneys to reabsorb sufficient water.

B. False Reabsorption of water in proximal tubules is normal since it depends on the active reabsorption of sodium; reabsorption in the collecting ducts is affected.

C. False Both fluid compartments are depleted in volume.

D. False It rises due to depletion of water but not salt.

E. False Both compartments show the same raised osmolality; osmotic gradients are effective in moving water at cell membranes.