Osmotic gradient???

Question

would someone be so kind as to briefly describe osmotic gradient and how it works in the kidney. if you could pretend i'm 5, that would be helpful. thanks

Answer 1

Funny that you say that. I said the exact same thing 6 months ago. I'm going to try to break this down as much as I can for you. As a Biology major, I can't promise you the simple answer that your looking for.

Say you have a semipermeable membrane. So, some molecules can go through it and others can't.On both sides, you have two solutions each with a certain concentration. The osmotic gradient is the difference between these solutions. The kidney's function is to adjust the volume and the osmolarity(total solute concentration) of urine, depending on the water and salt balance and the rate of urea production. Urea is a waste product, but it helps to form concentrated urine. How the osmotic gradient works within the kidney is somewhat complicated. I would suggest looking at the site below. It's meant to simplify it. I hope this helps!