Question

The presence of ADH (antidiuretic hormone) causes an individual to excrete a. sugars. b. less water. c. more water. d. Both a and c are correct.

Short answer

The correct answer is \(b. \text{less water}\). The presence of ADH increases the permeability of the collecting ducts to water in the kidneys, leading to more water being reabsorbed into the bloodstream and less water being excreted.

Step-by-step solution

Understanding ADH

Antidiuretic hormone (ADH), also known as vasopressin, is a hormone produced by the hypothalamus and stored in the posterior pituitary gland. Its primary function is to regulate the body's water balance by controlling the amount of water excreted through urine.

Option A - Sugars

ADH is specifically responsible for regulating water balance and does not have a direct role in the excretion of sugars. Therefore, option A is not correct.

Option B - Less Water

When ADH is released from the posterior pituitary gland, it acts on the kidneys to increase the permeability of the collecting ducts to water. This leads to more water being reabsorbed into the bloodstream, resulting in the production of more concentrated urine and the excretion of less water. This mechanism helps to conserve water in the body. So, option B is correct.

Option C - More Water

As we have discussed in option B, the presence of ADH causes an individual to excrete less water, not more water. Therefore, option C is not correct.

Option D - Both A and C are correct

As we have ruled out both options A and C, this option is also incorrect.

Conclusion

Based on the analysis, the presence of ADH (antidiuretic hormone) causes an individual to excrete less water, which corresponds to option B. Thus, the correct answer is option B.