In blood clothing, fibrins are formed from inactive fibrinogen by the enzyme

Options

A. thrombin
B. thrombokinase
C. creatine kinase
D. heparin

Answer

To solve the question about how fibrins are formed from inactive fibrinogen during blood clotting, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Components**:
- Fibrinogen is a soluble plasma protein that is converted into fibrin during the clotting process.
- Fibrin is an insoluble protein that forms a mesh-like structure, which is essential for blood clotting.

2. **Identifying the Enzyme**:
- The conversion of fibrinogen to fibrin is catalyzed by a specific enzyme. We need to identify this enzyme from the options provided.

3. **Options Analysis**:
- The options given are:
- a) Thrombin
- b) Thrombokinase
- c) Triatumkinase
- d) Heparin

4. **Correct Enzyme Identification**:
- Thrombin is the enzyme that converts inactive fibrinogen into fibrin. It acts on fibrinogen in the presence of calcium ions to facilitate this conversion.
- Thrombokinase is involved in the activation of prothrombin to thrombin, but it does not directly convert fibrinogen to fibrin.
- Triatumkinase is not a recognized enzyme in the context of blood clotting.
- Heparin is an anticoagulant that prevents clotting, rather than promoting it.

5. **Conclusion**:
- Based on the analysis, the correct answer to the question is **option a) thrombin**.

### Final Answer:
In blood clotting, fibrins are formed from inactive fibrinogen by the enzyme **thrombin**.

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