Flow of blood in the ventral vessel of earthworm is

Options

A. Forwards
B. Backwards
C. Backwards in half of it and forwards in another half
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understand the Circulatory System of Earthworm**: The earthworm has a closed circulatory system, which means that the blood circulates exclusively through vessels rather than flowing freely in a body cavity.

2. **Identify the Main Blood Vessels**: There are three main vessels involved in the circulation of blood in earthworms:
- Aortic arches
- Dorsal blood vessel
- Ventral blood vessel

3. **Function of Aortic Arches**: The aortic arches function similarly to a human heart. There are five pairs of these arches that pump blood into both the dorsal and ventral blood vessels.

4. **Role of the Dorsal Blood Vessel**: The dorsal blood vessel carries blood towards the anterior (front) part of the earthworm's body.

5. **Role of the Ventral Blood Vessel**: The ventral blood vessel is responsible for carrying blood towards the posterior (back) part of the earthworm's body.

6. **Determine the Direction of Blood Flow**: Since the ventral blood vessel carries blood to the back of the earthworm, the flow of blood in the ventral vessel is backwards.

7. **Final Answer**: Therefore, the flow of blood in the ventral vessel of the earthworm is backwards.

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