Conversion of soluble fibrin into insoluble fibrin is made possible in the presence of

Options

A. factor X
B. factor XIII
C. factor XII
D. factor IX

Answer

To solve the question regarding the conversion of soluble fibrin into insoluble fibrin, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Fibrinogen and Fibrin**:
- Fibrinogen is a soluble plasma protein that is converted into fibrin, which is an insoluble protein that forms the mesh structure of a blood clot.

2. **Role of Prothrombin**:
- Prothrombin is another protein in the blood that is converted into thrombin during the coagulation process. Thrombin plays a crucial role in the conversion of fibrinogen to fibrin.

3. **Clotting Factors**:
- The conversion of prothrombin to thrombin is facilitated by clotting factors. Among these factors, Factor 10 (also known as Factor X) is particularly important as it acts as a prothrombinase.

4. **Conversion Process**:
- Factor 10 (Factor X) converts prothrombin into thrombin. Once thrombin is formed, it then acts on fibrinogen to convert it into fibrin.

5. **Final Conversion**:
- The conversion of soluble fibrinogen into insoluble fibrin is thus dependent on the presence of thrombin, which is generated in the presence of Factor 10.

6. **Conclusion**:
- Therefore, the conversion of soluble fibrin into insoluble fibrin is made possible in the presence of Factor 10.

### Answer:
The conversion of soluble fibrin into insoluble fibrin is made possible in the presence of **Factor 10**.

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