Dropping of gravid proglottids by cestodes is called

Options

A. Autophagy
B. Autotomy
C. Paedogenesis
D. Apolysis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks about the term used for the dropping of gravid proglottids by cestodes (tapeworms). Gravid proglottids are segments of the tapeworm that contain fertilized eggs.

2. **Identifying the Process:** In cestodes, these segments regularly detach from the posterior end of the strobila (the body of the tapeworm). This process is important for the reproduction and life cycle of the tapeworm.

3. **Reviewing the Options:** The options provided are:
- Autophagy
- Autotomy
- Pedogenesis
- Apolysis

4. **Analyzing Each Option:**
- **Autophagy:** This refers to the process of self-digestion by cells, not related to proglottid shedding.
- **Autotomy:** This is the ability of an organism to shed a part of its body, typically for defense, not specifically related to proglottids.
- **Pedogenesis:** This refers to reproduction by juvenile forms, which does not apply to the shedding of proglottids.
- **Apolysis:** This term specifically refers to the shedding or dropping of proglottids from the tapeworm.

5. **Conclusion:** After analyzing the options, the correct term for the dropping of gravid proglottids by cestodes is **apolysis**. This process allows the tapeworm to transfer developing embryos to the exterior environment, where they can be ingested by a secondary host, and it also helps limit the size of the tapeworm's body.

**Final Answer:** The dropping of gravid proglottids by cestodes is called **apolysis**.

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