Question

In the kidneys, the __(i)__ and the __(ii)__ mechanisms occur. The first takes place in a region of the nephron called __(iii)__; the second occurs in a region of the peritubular capillary bed called the ___(iv)___

• A. i- Countercurrent multiplier, ii - Countercurrent exchanger, iii - Henle's loop, iv - Vasa recta.
• B. i - Countercurrent exchanger, ii - Countercurrent multiplier, iii - Henle's loop, iv - Vasa recta.
• C. i - Countercurrent multiplier, ii - Countercurrent exchanger, iii - Vasa recta, iv - Henle's loop.
• D. i - Countercurrent exchanger, ii - Countercurrent multiplier, iii - Vasa recta, iv - Henle's loop.

Answer 1

The correct option is A i- Countercurrent multiplier, ii - Countercurrent exchanger, iii - Henle's loop, iv - Vasa recta.

The mechanisms shown here are traditionally called the 'countercurrent multiplier' and the 'countercurrent exchanger'. The first takes place in a region of the nephron called Henle's loop; the second occurs in a region of the peritubular capillary bed called the 'Vasa recta'. Both are involved in establishing respective osmotic gradients throughout this region.