The main function of Henle's loop is

Given below are two statements with respect to counter current mechanism.
$Statement-I$: Tissue fluid around the descending limb of Henle's loop becomes concentrated, during the counter current mechanism.
$Statement-II$: Water moves out from the descending limb of Henle's loop into the tissue fluid by osmosis.
In the light of the above statements, select the correct option from the codes given below:

Salmon have gills that are more permeable to water than to salts. Salmon hatch in fresh water streams and then migrate to the ocean. Once they reach the ocean,you would expect the rate of uptake of water into their body through the gills to:

Indicate whether the following statement is true or false:
Henle's loop plays an important role in concentrating the urine.

Which one of the following animals has a longer loop of Henle?

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