The descending limb of the loop of Henle is permeable to ........ .

Which ions enter the vasa recta?

In the given diagram,what are the regions $P, Q,$ and $R$?
$P \quad\quad Q \quad \quad R$

If Henle's loop were absent from mammalian nephron,which of the following is to be expected?

The proximity between Henle's loop and vasa-recta as well as the counter-current in them help in maintaining an ...$A$... in molarity towards the inner medullary interstitium,i.e.,from ...$B$... $mOsmol \ L^{-1}$ in the cortex to about ...$C$... $mOsmol \ L^{-1}$ in the inner medulla. Here $A$,$B$,and $C$ refer to:

If the kidneys fail to reabsorb water,what will be the effect on the tissues?