In Pheretima, clitellum is primarily meant for

Options

A. Burrowing
B. Fertilization
C. Producing cocoons
D. Locomotion

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question refers to Pheretima, which is the scientific name for the earthworm.

2. **Locate the Clitellum**: The clitellum is a specific structure in earthworms, located in segments 14 to 16 from the anterior end. It is characterized by being a thick glandular tissue sheet.

3. **Understand the Function of the Clitellum**: The primary function of the clitellum is related to reproduction. It secretes substances that help in the formation of a cocoon.

4. **Cocoon Formation Process**: During reproduction, the earthworm secretes a membranous girdle around the clitellar region. The earthworm then pulls its body out of this girdle, which slips over the oviductal and spermathecal apertures, allowing for the discharge of ova and sperm.

5. **Closure of the Cocoon**: After the ova and sperm are released, the open ends of the girdle close due to elasticity, forming a cocoon where fertilization and development occur.

6. **Conclusion**: Therefore, the clitellum in Pheretima is primarily meant for producing cocoons.

**Final Answer**: The clitellum in Pheretima is primarily meant for producing cocoons.

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