Question

Explain the principle of dialysis with the help of a labelled diagram.

Answer 1

Principle of dialysis:

The procedure of dialysis is based on the diffusion of solutes and the ultrafiltration of fluid across a semi-permeable membrane. In dialysis, the blood from a convenient artery is pumped into the dialyser of a dialysing machine. A dialyser contains a coiled cellophane tube surrounded by the dialysing solution. The dialysing solution contains water, glucose and salts, which are similar in concentration to those in normal blood. The porous cellophane membrane of the tube allows the passage of molecules based on concentration gradient. As the patient’s blood passes through the dialysing solution, most of the waste products (like urea) present in it pass through the selectively permeable cellulose tubes into the dialysing solution, thereby cleaning the blood. The clean blood is pumped back to the body through a vein.