Difficulty: Easy

Average Score: 75%

Which of the following physiological responses is caused by the release of anti-diuretic hormone?

Rationale

Increase in water reabsorption in the collecting duct.

Anti-diuretic hormone (ADH), also known as vasopressin, acts primarily on the kidneys to promote water reabsorption in the collecting ducts. This process conserves water in the body, thus concentrating urine and reducing urine volume.

A (Decrease in water reabsorption in the collecting duct) YOUR ANSWER

ADH functions by enhancing the permeability of the collecting duct to water, thereby facilitating water reabsorption. A decrease in water reabsorption would contradict the action of ADH, which is aimed at retaining water rather than expelling it.

B (Decrease in the concentration of calcium in the glomerulus) YOUR ANSWER

Calcium concentration in the glomerulus is primarily influenced by factors such as dietary intake and parathyroid hormone, not directly by ADH. ADH's role is focused on water balance, making this choice irrelevant regarding its physiological effects.

C (Increase in the concentration of calcium in the glomerulus) YOUR ANSWER

Similar to choice B, the concentration of calcium in the glomerulus is not modulated by ADH. Instead, it is regulated by other hormones, such as parathyroid hormone, and is unrelated to the actions of ADH, which promotes water reabsorption.

D (Increase in water reabsorption in the collecting duct) CORRECT

ADH increases the permeability of the collecting ducts to water by stimulating the insertion of aquaporin channels in the renal tubule cells. This leads to enhanced water reabsorption, which is critical for maintaining body fluid balance and concentrating urine.

Conclusion

The physiological response induced by anti-diuretic hormone (ADH) is an increase in water reabsorption in the collecting duct. This mechanism plays a vital role in regulating fluid balance in the body, allowing for the conservation of water and the production of concentrated urine. The other options incorrectly attribute effects to ADH that are not relevant to its primary function in the renal system.

Related Questions

View all