Final answer:
In hemodialysis, dialysate is a solution that typically contains sterile water, glucose, amino acids, and certain electrolytes. It has a lower solute concentration than blood to enable efficient diffusion of urea and other waste substances from the blood into the dialysate.
Step-by-step explanation:
Components of Dialysate
Patients with kidney illnesses use hemodialysis to remove harmful toxins such as urea from their blood. Dialysate, a crucial component of this process, is a solution made up of sterile water, glucose, amino acids, and specific electrolytes. In the dialyzer, the blood is exposed to the dialysate across a semipermeable membrane, allowing for diffusion of waste substances from the blood into the dialysate.
The concentration of solutes in the dialysate plays a vital role in the efficiency of the hemodialysis. Generally, the dialysate should have a lower solute concentration compared to the blood, particularly of substances like urea, to facilitate their diffusion down the concentration gradient (d). The purpose of this gradient is to effectively remove waste substances via the process of osmosis, where fluid balance is also maintained.
By design, the dialysate assists in the removal of excess urea and maintains optimal levels of essential substances. The semipermeable membrane of the dialyzer allows small molecules and ions to pass but retains larger colloidal particles like proteins within the blood (a, b, c, d). The blood, after traveling through the dialysis machine and interacting with the dialysate, returns to the body devoid of excessive waste materials.