Which of the following statements is incorrect about metagenesis ?

Options

A. Alternation of asexual and sexual phases in the life cycle of Obelia is called metagenesis
B. Metagenesis is similar to alternation of generations as found in plants
C. Both the medusa and polyp are diploid
D. Medusa is the sexual phase and polyp is the asexual phase

Answer

To determine which statement about metagenesis is incorrect, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Understanding Metagenesis**:
- Metagenesis refers to the alternation of generations in the life cycle of certain organisms, particularly in some cnidarians like Obelia. It involves a switch between asexual and sexual reproduction.

2. **Analyzing the Statements**:
- **Statement 1**: "Alteration of asexual and sexual phases in the life cycle of Obelia is called metagenesis."
- This statement is **correct**. Metagenesis indeed involves the alternation between asexual (polyp) and sexual (medusa) forms in the life cycle of Obelia.

- **Statement 2**: "Metagenesis is similar to alteration of generation as found in plants."
- This statement is **incorrect**. While both concepts involve alternation of generations, metagenesis specifically refers to the life cycles of certain animals and is distinct from the plant life cycle alterations.

- **Statement 3**: "Both medusa and polyp are diploid."
- This statement is **correct**. In the life cycle of Obelia, both the medusa (sexual phase) and the polyp (asexual phase) are diploid.

- **Statement 4**: "Medusa is the sexual phase and polyp is the asexual phase."
- This statement is **correct**. The medusa stage is indeed the sexual phase, while the polyp stage is the asexual phase in the life cycle of Obelia.

3. **Conclusion**:
- The incorrect statement about metagenesis is **Statement 2**: "Metagenesis is similar to alteration of generation as found in plants."

### Final Answer:
The incorrect statement about metagenesis is **Statement 2**.

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