Which of the blood vessel may be considered as true heart in earthworm ?

Options

A. dorsal blood vessel
B. ventral blood vessel
C. supra-oesophageal blood vessel.
D. Anterior loop.

Answer

**Step-by-Step Solution:**

1. **Identify the Blood Vessels in Earthworm:**
- Earthworms have several blood vessels, including the dorsal blood vessel, ventral blood vessel, supraesophageal blood vessel, and anterior lobe.

2. **Understand the Function of Each Vessel:**
- The dorsal blood vessel is located on the dorsal side of the earthworm and is responsible for transporting blood.
- The ventral blood vessel runs along the ventral side and also plays a role in circulation.
- The supraesophageal blood vessel is involved in supplying blood to the head region.
- The anterior lobe is not a blood vessel but rather a part of the earthworm's anatomy.

3. **Determine Which Vessel Functions as a Heart:**
- The dorsal blood vessel has thick walls and is responsible for pumping blood into the aortic arches, which are essential for circulation.

4. **Conclude the Answer:**
- Based on its structure and function, the dorsal blood vessel can be considered the true heart of the earthworm.

**Final Answer:** The dorsal blood vessel may be considered as the true heart in earthworm.

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