Question

Question 7 1 pts The hormone ADH stimulates water reabsorption at the ... The PCT and DCT The DCT and collecting duct The descending limb of the Loop of Henle and collecting duct Collecting duct only

Answer 1

• Answer : Both DCT and collecting duct.

ADH (anti diuretic hormone) helps to reabsorb water from the distal convoluted tubule and collecting duct. This is because the DCT and collecting duct are more permiabe to water (they posses aqua porins).

ADH helps in the water reabsorption only in the DCT and collecting duct and not in PCT. In PCT the water reabsorption occurs along with glucose, pottasium, chloride, sodium amino acid etc. In PCT it happens via active or passive transport.

Descending limb of henley's loop donot reabsorb water. It removes water via osmosis since there is a hypertonic environment.

• Answer : Renal glucose reabsorption requires insulin. Type 1 DM patients lack insulin and do not activate glucose reabsorption.

In type 1 Diabetes Mellitus patients, the pancreas donot produce insulin. Insulin helps in the absorption of glucose into cells. With out insulin, glucose cannot be reabsorbed in the renal tubule also. Hence the glucose accumulates in the urine and excreated through urine.

DM patients due to lack renal glucose transporters.

They donot excrete excess glucose. excess glucose comes in blood only due to the lack of cellular absorption of glucose.

It is not because of the fact that the transporters are saturated due to high glucose content but it is the failure in reabsortion of glucose due to lack of insulin.