Same chapter3 marksDifficulty: Medium
Name the hormones that regulate kidney function and state what each does.
Excretory Products and their Elimination
3 marksDifficulty: Medium
Explain the counter-current mechanism in the kidney.
Original Khojo Papers practice question — not from a past board paper.
Answer
The limbs of the loop of Henle carry filtrate in opposite directions and lie close to the vasa recta, which carries blood in the opposite direction to the neighbouring limb. This arrangement maintains a steep concentration gradient in the medulla from the cortex inwards, so that water can be drawn out of the collecting duct and a concentrated urine produced.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The gradient is maintained by the active transport of sodium and the recycling of urea.
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