Waste products are removed during dialysis by which principle?

Waste products are removed during dialysis by which principle?

• A. Diffusion
• B. Ultrafiltration
• C. Osmosis
• D. Dialysis

Answer: (B)

In dialysis, waste products are removed primarily by diffusion. This means small solutes like urea and creatinine move from blood, where their concentration is higher, across the semipermeable membrane into the dialysate, which has a lower concentration. The membrane allows these small particles to pass while retaining larger proteins and blood cells. Ultrafiltration, on the other hand, is the process of removing excess fluid from the blood by applying pressure across the membrane. It pulls water out of the blood (and can drag some solutes with it by convection), but it is not the main mechanism for clearing dissolved waste products. So, waste product clearance relies on diffusion, while ultrafiltration is responsible for fluid removal.

In dialysis, waste products are removed primarily by diffusion. This means small solutes like urea and creatinine move from blood, where their concentration is higher, across the semipermeable membrane into the dialysate, which has a lower concentration. The membrane allows these small particles to pass while retaining larger proteins and blood cells.

Ultrafiltration, on the other hand, is the process of removing excess fluid from the blood by applying pressure across the membrane. It pulls water out of the blood (and can drag some solutes with it by convection), but it is not the main mechanism for clearing dissolved waste products.

So, waste product clearance relies on diffusion, while ultrafiltration is responsible for fluid removal.