Question

Which of the following statements about aldosterone is NOT correct? View Available Hint(s) Which of the following statements about aldosterone is NOT correct? Aldosterone is stimulated by decreased plasma sodium levels and increased plasma potassium levels. Aldosterone increases the number of passive sodium channels in the luminal membrane of the distal tubule and collecting duct, thus aiding sodium reabsorption. Aldosterone is produced in the adrenal cortex. Aldosterone increases sodium reabsorption by increasing the number of Na+-K+ ATPase pumps in the luminal membrane of the proximal tubule.

Answer 1

Answer:

C. Aldosterone increases sodium reabsorption by increasing the number of Na+-K+ ATPase pumps in the luminal membrane of the proximal tubule.

Explanation:

The terminal part of distal convoluted tubules has two different types of cells: principal cells and intercalated cells. These cells are also present throughout the collecting duct. The principal cells serve to reabsorb Na+ and secrete K+ and have receptors for aldosterone and antidiuretic hormone (ADH).

The function of intercalated cells reabsorb HCO3 - and K+ and to secrete H+. Angiotensin II stimulates the adrenal cortex to release aldosterone which in turn stimulates the principal cells in the collecting ducts to reabsorb more Na+ and secrete more K+. The increased reabsorption of Na+ facilitates reabsorption of more water to increase blood volume and blood pressure.