Blood dialysis is called `:`

Options

A. Artificial lung
B. Artificial kidney
C. Artificial heart
D. Artificial brain

Answer

**Step-by-Step Solution:**

1. **Understanding Blood Dialysis**: Blood dialysis is a medical procedure that involves the purification of blood by removing nitrogenous waste products. This is particularly important for individuals whose kidneys are not functioning properly.

2. **Identifying the Equipment**: The process of blood dialysis is performed using a machine that mimics the function of the kidneys. This machine is often referred to as an "artificial kidney".

3. **Mechanism of Action**: In blood dialysis, blood is pumped into a chamber that contains a semi-permeable membrane (often made of cellophane). This membrane allows certain substances to pass through while blocking others.

4. **Role of the Dialysis Fluid**: Inside the chamber, there is a special dialysis fluid that has a composition similar to blood but lacks nitrogenous waste products. This creates a concentration gradient.

5. **Purification Process**: Due to the concentration difference, nitrogenous wastes from the blood move through the semi-permeable membrane into the dialysis fluid, effectively purifying the blood.

6. **Returning Purified Blood**: After the blood has been purified, it is returned to the patient’s body, similar to how healthy kidneys would function.

7. **Conclusion**: Given this understanding, blood dialysis is correctly referred to as "artificial kidney".

**Final Answer**: Blood dialysis is called **artificial kidney**.

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