Which of the following formed element activates the plasma clotting factors ?

Options

A. Erythrocytes
B. Monocytes
C. Lymphocytes
D. Thrombocytes

Answer

To solve the question "Which of the following formed element activates the plasma clotting factors?", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Formed Elements of Blood**:
- Blood consists of several formed elements, including erythrocytes (red blood cells), leukocytes (white blood cells), and thrombocytes (platelets).

2. **Understand the Function of Each Element**:
- **Erythrocytes**: These are red blood cells primarily responsible for transporting oxygen throughout the body due to the presence of hemoglobin.
- **Leukocytes**: This category includes monocytes and lymphocytes, which are types of white blood cells. They play crucial roles in the immune response and are involved in fighting infections. They are also phagocytic, meaning they can engulf and digest pathogens.
- **Thrombocytes**: Also known as platelets, these are small cell fragments derived from megakaryocytes. Their main function is to facilitate blood clotting.

3. **Focus on Clotting Factors**:
- The question specifically asks about the activation of plasma clotting factors. This is a process essential for the formation of blood clots to prevent excessive bleeding.

4. **Identify the Correct Formed Element**:
- Among the options provided (erythrocytes, monocytes, lymphocytes, and thrombocytes), thrombocytes (platelets) are known to activate plasma clotting factors. They play a critical role in the hemostatic process, which involves the formation of a clot.

5. **Conclusion**:
- Based on the functions of the formed elements, the correct answer is **thrombocytes (option D)**, as they are responsible for activating the plasma clotting factors and initiating the clotting process.

### Final Answer:
**Thrombocytes (option D)** activate the plasma clotting factors.

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