Dorsal vessel of Earthworm is

Options

A. Distributing
B. Collecting
C. Collecting in first 13 segments and distributing in the rest
D. Distribution in first 13 segments and collecting in the rest

Answer

**Step-by-Step Solution:**

1. **Understanding the Earthworm's Circulatory System:**
- Earthworms possess a closed circulatory system, which means that blood is contained within vessels and does not flow freely in the body cavity.

2. **Identifying the Dorsal Vessel:**
- The dorsal vessel is one of the main blood vessels in the earthworm. It runs along the back (dorsal side) of the earthworm.

3. **Function of the Dorsal Vessel:**
- The dorsal vessel has two primary functions:
- In the first 13 segments of the earthworm, it acts as a **distributing vessel**, meaning it helps distribute blood throughout these segments.
- In segments 14 and onward, the dorsal vessel functions as a **collecting vessel**, meaning it collects blood from the segments and directs it towards the heart.

4. **Comparing with Other Vessels:**
- The ventral blood vessel is the main distributing vessel in the earthworm's circulatory system. It carries blood to various parts of the body, including the buccal cavity, pharynx, and gizzard.

5. **Conclusion:**
- Therefore, the correct answer to the question about the dorsal vessel of the earthworm is that it **collects in the first 13 segments and distributes in the rest**.

**Final Answer:**
The dorsal vessel of the earthworm is **collecting in the first 13 segments and distributing in the rest**.

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