Question

Describe how an osmotic gradient is set up inside the medullary pyramids.

Answer 1

Osmotic gradient is set up by counter current mechanism

• Active transport of ions from the collecting duct into the medullary interestitium
• Facilitated diffusion of large amount of area from the inner medullary collecting duct into the medullary interestitium
• Diffusion of small amount of water from medullary tubules into the interestitium
• Active transport of sodium ions and co transport of potassium, chlorine,and other ions out of the thick portion of ascending limb of loop of Henle