Question

select the correct answer
dora is feeling weak and parched after a long day of hiking in the hot sun. when she urinates, she notices it is only a scant amount. in what way have
doras kidneys adjusted to maintain her bodys homeostasis?
a. kidneys have begun to fail and she must be treated for acute renal failure immediately
b. kidneys have produced concentrated urine and reabsorbed as much water as possible
c. kidneys have produced diluted urine and have eliminated all excess water
d. kidneys have begun to develop numerous large cysts and will begin failing immediately
e. kidneys have suddenly developed the condition of nephrolithiasis and she will have to pass kidney stones

Explanation:

When the body is dehydrated (like after a long day of hiking in the hot sun), the kidneys work to conserve water. They reabsorb more water from the filtrate in the nephrons. This results in the production of concentrated urine (less volume) as the body tries to maintain homeostasis (a stable internal environment). Option A is incorrect as acute renal failure would be a more severe and different condition. Option C is wrong because in a dehydrated state, the body does not produce diluted urine to eliminate excess water (there is no excess water in this case). Option D about cysts is not related to the normal homeostatic response to dehydration. Option E about nephrolithiasis (kidney stones) is also not related to the immediate homeostatic adjustment for water balance during dehydration.

Answer:

B. kidneys have produced concentrated urine and reabsorbed as much water as possible