Prostatic secretion is used in earthworm for

Options

A. Sperm activation
B. Ootheca
C. Spermatophore layer
D. Copulation

Answer

**Step-by-Step Solution:**

1. **Understanding Prostatic Secretion in Earthworms:**
Prostatic secretion in earthworms is produced in specific segments of their body, particularly segments 17 to 19. This secretion plays a crucial role in reproduction.

2. **Role of Prostatic Secretion:**
The prostatic secretion is a component of the semen in earthworms. It has several important functions during the reproductive process.

3. **Functions of Prostatic Secretion:**
- **Lubrication:** The secretion provides lubrication, which is essential for making the sperm more soluble and facilitating its movement.
- **Ejection of Semen:** It aids in the ejection of the semen during reproduction, ensuring that sperm can be effectively transferred.
- **Sperm Activation:** The prostatic secretion also plays a role in activating the sperm, enhancing its motility and readiness for fertilization.

4. **Composition of Semen:**
It is noted that a significant portion (about 70%) of the semen is linked to these activities facilitated by the prostatic secretion.

5. **Conclusion:**
In summary, prostatic secretion in earthworms is vital for lubrication, the ejection of semen, and the activation of sperm, all of which contribute to successful reproduction.

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