Question

How does the Loop of Henle create a concentration gradient in the mammalian kidney?

Answer 1

Loop of henle plays major role in maintaining concentration gradient

i) loop of henle has 2 divisions descending and ascending loop of henle .

Descending loop of henle is permeable to water and impermeable to ions , so more water reabsorbed and the fluid becomes more concentrated

Ascending loop of henle more permeable to ions but not to water so maintenance of electrolyte balance

ii) counter current mechanism : main mechanism to concentrate urine . It is a u shaped tube where fluid flows in opposite directions . It is formed by both loop of henle and vasa recta

The sodium , chloride and potassium ions move from the ascending limb into the descending limb of vasa recta and creates concentration gradient down the Vasa recta and these ions enters the medullary interstitium and the water secreted from the descending loop of henle is exchanged at the ascending vasa recta by secreting these ions into the medullary interstitium

By the transport of ions and water concentration gradient is.created at in the loop of henle