THE MECHANISM OF CONCENTRATION OF FILTRATE IS KNOWN AS COUNTER CURRENT MECHANISM. JUSTIFY THE STATEMENT.

Henle's loop and vasa recta play a vital role in the counter current mechanism. Henle's loop and vasa recta have two limbs and in these two limbs the filtrate flows in the opposite direction. Thus forms a counter current pattern.

The counter current mechanism operating inside the kidney is the main adaptation for the conservation of water. There are two counter current mechanisms inside the kidneys. They are Henle’s loop and vasa rectae.

Henle’s loop is a U-shaped part of the nephron. Blood flows in the two limbs of the tube in opposite directions and this gives rise to counter currents. The Vasa recta is an efferent arteriole, which forms a capillary network around the tubules inside the renal medulla. It runs parallel to Henley’s loop and is U-shaped. Blood flows in opposite directions in the two limbs of vasa recta. As a result, blood entering the renal medulla in the descending limb comes in close contact with the outgoing blood in the ascending limb.