For conversion of prothrombin into thrombin, which of the following is required

Options

A. Fibrinogen
B. Vitamin K.
C. Proconvertin
D. Thrombokinase

Answer

To answer the question regarding the conversion of prothrombin into thrombin, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Prothrombin and Thrombin**:
- Prothrombin is an inactive precursor of thrombin, which is a crucial enzyme in the blood coagulation process.

2. **Role of Thrombin**:
- Thrombin is responsible for converting fibrinogen into fibrin, which is essential for blood clot formation.

3. **Identifying the Conversion Process**:
- The conversion of prothrombin to thrombin is a critical step in the coagulation cascade.

4. **Components Required for Conversion**:
- The conversion of prothrombin to thrombin requires specific factors. Among the options provided (fibrinogen, vitamin K, pro-convertin, and thrombokinase), we need to identify which one is essential for this conversion.

5. **Thrombokinase**:
- Thrombokinase, also known as prothrombinase, is an enzyme complex that catalyzes the conversion of prothrombin into thrombin.

6. **Conclusion**:
- Therefore, the correct answer to the question is that thrombokinase is required for the conversion of prothrombin into thrombin.

### Final Answer:
The component required for the conversion of prothrombin into thrombin is **thrombokinase**.

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