The correct statement about dialysis is :

Options

A. It acts as a permanent treatment solution to treat people with end - stage kidney disease.
B. The dialysing unit into which the blood is drained contains heparin to prevent coagulation.
C. The cellophane tube is surrounded by a dialysing fluid , which has the same concentration as plasma including the nitrogenous waste.
D. Dialysis replaces all of the functions of the kidney through diffusion. Ultrafiltration and tubular secretion.

Answer

To solve the question regarding the correct statement about dialysis, we will analyze the provided statements one by one based on our understanding of the dialysis process.

### Step-by-Step Solution:

1. **Understanding Dialysis**:
- Dialysis is a medical procedure that mimics the natural function of the kidneys. It is primarily used when the kidneys are unable to filter waste products from the blood effectively.

2. **Analyzing the Statements**:
- **Statement 1**: "Dialysis is a permanent treatment for end-stage kidney disease."
- This statement is incorrect. Dialysis is not a permanent solution; it must be performed repeatedly to manage waste products in the blood.

- **Statement 2**: "In the dialysing unit, the blood that is drained from the body contains heparin to prevent coagulation."
- This statement is correct. Heparin is an anticoagulant that is added to the blood before it enters the dialysis machine to prevent clotting.

- **Statement 3**: "The cellophane tube is surrounded by dialyzing fluid, in which all the same concentrations are there like blood plasma."
- This statement is incorrect. The dialyzing fluid is similar to blood plasma but lacks nitrogenous waste, which allows for the removal of these wastes from the blood.

- **Statement 4**: "Dialysis replaces all the functions of the kidney with diffusion, ultrafiltration, and tubular secretion."
- This statement is also incorrect. While dialysis does involve diffusion and ultrafiltration, it does not replicate all the complex functions of the kidneys, such as tubular secretion.

3. **Conclusion**:
- After analyzing all the statements, the only correct statement about dialysis is **Statement 2**: "In the dialysing unit, the blood that is drained from the body contains heparin to prevent coagulation."

### Final Answer:
The correct statement about dialysis is **Option B**.

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