Alternation of generation shown by coelenterates is termed

Options

A. metastasis
B. metaphysis
C. metamorphosis
D. metagenesis

Answer

To solve the question regarding the term that describes the alternation of generation shown by coelenterates, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terms**: First, we need to clarify the terms provided in the question: metastasis, metaphysis, metamorphosis, and metagenesis.
- **Metastasis**: This refers to the spread of cancer from one part of the body to another.
- **Metaphysis**: This is a part of a long bone where growth occurs.
- **Metamorphosis**: This is the process of transformation from larva to adult form in certain organisms.
- **Metagenesis**: This refers to the alternation of generations between asexual and sexual phases in certain organisms.

2. **Identify the Relevant Term**: The question specifically asks about the alternation of generations in coelenterates (also known as cnidarians).
- Coelenterates exhibit a life cycle that includes both asexual and sexual reproduction phases.

3. **Connect the Definition**: Since metagenesis describes the alternation between asexual and sexual phases, it directly relates to the life cycle of coelenterates.
- In coelenterates, the polyp form can reproduce asexually, while the medusa form can reproduce sexually.

4. **Conclusion**: Based on the definitions and the life cycle of coelenterates, the correct answer to the question is **metagenesis**.

### Final Answer:
The alternation of generation shown by coelenterates is termed **metagenesis**.

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