In earthworm the segment bearing mouth is called

Options

A. Deuterostomium
B. Prostomium
C. Peristomium
D. Stomium

Answer

**Step-by-Step Solution:**

1. **Understanding the Structure of Earthworm**: The earthworm is a segmented organism belonging to the phylum Annelida. Each segment of the earthworm has specific structures and functions.

2. **Identifying the Mouth Location**: The mouth of the earthworm is located at the anterior end (the front end) of its body. This is the first segment of the earthworm.

3. **Defining the Segment with the Mouth**: The segment that bears the mouth is not distinctly segmented like the other body segments. Instead, it is a specialized structure.

4. **Naming the Segment**: The segment that contains the mouth is called the "peristomium." The term "peri" means around or near, indicating its position at the front or anterior side of the earthworm.

5. **Conclusion**: Therefore, the segment bearing the mouth in an earthworm is known as the peristomium.

**Final Answer**: The segment bearing the mouth in an earthworm is called the **peristomium**.

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