ANSWER KEY TO RENAL WATER REGULATION PRACTICE QUESTIONS

1. C The increased ADH release would lead to increased water reabsorption from the later distal tubule and collecting ducts, so urine formation rate would decrease.

2. D

3. C Ethanol inhibits release of ADH from the posterior pituitary, so a large volume of dilute urine would be excreted.

4. B Drinking two liters of sea water would increase extracellular osmolality, thus stimulating hypothalamic osmoreceptors and leading to a greater increase of ADH release than drinking two liters of the other solutions indicated.