The glomerular filtrate in the loop of Henle gets concentrated in the descending and then gets diluted in the ascending limbs. Explain.

(N/A) Descending Limb of the Loop of Henle: This part is highly permeable to $H_2O$ (water) but impermeable to electrolytes. As the filtrate moves down into the hypertonic medullary interstitium,water is reabsorbed by osmosis,which concentrates the filtrate.
Ascending Limb of the Loop of Henle: This part is impermeable to water but allows the transport of electrolytes (like $Na^+$,$Cl^-$) either actively or passively. As the concentrated filtrate moves upward,the removal of electrolytes causes the filtrate to become diluted.