Question

which of the following organs will work to correct the homeostatic imbalances in dehydration, hypovolemia or hemorrhage?

A) the lungs

B) the kidneys

C) the adrenal glads

D) the pancreas

E) the thyroid gland

Answer 1

Dehydration, hypovolemia and hemorrhage all lead to decrease in blood volume.
When blood volume decreases, the blood flow to the kidneys reduces. This stimulates kidneys to release renin which acts on the liver to produce angiotensinogen. The angiotensinogen is further converted to angiotensin l by renin. Angiotensin l is then converted to angiotensin ll to in the presence of angiotensin converting enzyme. The angiotensin then acts on the adrenal gland to release aldosterone. Aldosterone then acts on blood vessels to constrict and increases reabsorption of sodium and water from renal tubules. Aldosterone further acts on pituitary gland to release ADH which increases water retention. This results in increasing blood volume and water conservation which helps in correcting hemorrhage, hypovolemia and dehydration.
The adrenal gland also gets activated and release adrenaline and noradrenaline to increase sympathetic activity. This results vasoconstriction and increased myocardial activity to increase stroke volume and cardiac output. This also helps in increasing blood volume.
So the organs that help in correcting homeostatic imbalances in dehydration, hypovolemia or Hemorrhage are :

B) the kidneys

C) the adrenal glads