Thromboplastin is secreated by `:-`

Options

A. Kidney
B. Platelets
C. Leucocyte
D. Erythrocyte

Answer

**Step-by-Step Solution:**

1. **Understanding Thromboplastin**:
- Thromboplastin, also known as thrombokinase, is a crucial factor involved in the blood clotting process. It plays a significant role in converting prothrombin into thrombin.

2. **Identifying the Source**:
- The question asks where thromboplastin is secreted from. The options provided are kidney, platelets, leukocytes, and erythrocytes.

3. **Analyzing Each Option**:
- **Kidney**: The kidneys are not involved in the secretion of thromboplastin; they have different functions related to filtration and urine production.
- **Platelets**: Platelets, also known as thrombocytes, are small cell fragments in the blood that are crucial for clotting. They secrete thromboplastin, making this option a strong candidate.
- **Leukocytes**: These are white blood cells involved in the immune response. They do not secrete thromboplastin.
- **Erythrocytes**: Red blood cells (RBCs) are primarily responsible for transporting oxygen and do not play a role in the secretion of thromboplastin.

4. **Conclusion**:
- Based on the analysis, the correct answer is that thromboplastin is secreted by **platelets**.

**Final Answer**: Thromboplastin is secreted by **platelets**.

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