Which trace mineral would best be increased for a PN-dependent patient with intractable diarrhea?

Correct Answer: A

Rationale: Intractable diarrhea leads to significant zinc loss via the stool. For a PN-dependent patient, increasing zinc supplementation is critical to prevent deficiency and support wound healing and immune function.

Correct Answer: A

Rationale: Kidneys adjust water and ion reabsorption slowly in response to blood volume changes, relying on hormonal signals like aldosterone and vasopressin.

Correct Answer: D

Rationale: Water reabsorption in the kidneys occurs via osmosis, driven by osmotic gradients created by ion reabsorption.

Correct Answer: B

Rationale: Osmoreceptors shrink and depolarize when plasma osmolarity increases, signaling dehydration.

Correct Answer: D

Rationale: Granular cells in the juxtaglomerular apparatus secrete renin to initiate the renin-angiotensin system.