Metaboly is characteristic of

Options

A. Amoebids
B. Heliozoans
C. Euglenoids
D. Dinoflagellates.

Answer

**Step-by-Step Solution:**

1. **Understanding Metaboly**: Metaboly refers to the ability of certain organisms to change their shape and move in a fluid manner. This characteristic is particularly notable in certain types of unicellular eukaryotes.

2. **Identifying the Organisms**: The question provides four options: amoeboids, heliozoans, euglenoids, and dinoflagellates. We need to determine which of these groups exhibits metaboly.

3. **Analyzing Each Group**:
- **Amoeboids**: These organisms, such as amoeba, are known for their ability to change shape through pseudopodia, but this is not specifically referred to as metaboly.
- **Heliozoans**: These are mostly spherical and do not exhibit significant shape-changing movements like metaboly.
- **Euglenoids**: This group, which includes organisms like Euglena, is known for their characteristic shape-changing motion. They can glide and swim using flagella, which contributes to their ability to change shape.
- **Dinoflagellates**: While they have unique movements, they do not exhibit metaboly in the same way euglenoids do.

4. **Conclusion**: Based on the analysis, the characteristic of metaboly is specifically associated with euglenoids. Therefore, the correct answer is euglenoids.

**Final Answer**: Metaboly is characteristic of euglenoids.

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