Question

Explain the concentration of glomerular filtrate​

Answer 1

Answer

The flow of glomerular filtrate in the two limbs of Henle's loop and the flow of blood through the two limbs of vasa recta are in counter current pattern.

$\bigstar$ The proximity between the Henle’s loop and vasa recta and the counter current in them maintains higher osmolarity towards the inner medullary interstitium than in the cortex.

$\bigstar$ This gradient is mainly caused by NaCl and urea.

$\bigstar$ NaCl is transported by the ascending limb of Henle's loop which is exchanged with the descending limb of vasa recta.

$\bigstar$ NaCl is returned to the interstitium by the ascending portion of vasa recta.

$\bigstar$ Similarly, small amounts of urea enter the thin segment of the ascending limb of Henle's loop which is transported back to the interstitium by the collecting tubule.