Question

More ADH means

• A. Less permeable DCT
• B. Concentrated urine
• C. Dilute urine
• D. Fall in blood osmotic pressure

Answer 1

The correct option is B

Concentrated urine

The correct option is B :

The explanation for the correct option:

1. Antidiuretic Hormone (ADH) is synthesized by hypothalamus and stored in the posterior pituitary.
2. ADH acts on the Distal convoluted tubule (DCT) and the collecting ducts and increases the re-absorption of water ($H_{2}O$).
3. ADH prevents the production of a large volume of dilute urine. Hence, it leads to the production of concentrated urine.

The explanation for the incorrect options:

Option A :

Less permeable distal convoluted tubule means less re-absorption of water, $HC{O}_3^{-}$and $K^{+}$ions, resulting in the formation of more diluted urine.

Option C :

Less production of ADH leads to less re-absorption of water by the capillary network surrounding the tubule. Thus, more and dilute urine is formed.

Option D:

Fall in the blood osmotic pressure is due to pressure opposing glomerular filtration, blood colloidal osmotic pressure, and capsular Hydrostatic pressure.

Final answer: More ADH means concentrated urine.