What are the characteristic features of Euglenoids?

Explanation

**Step-by-Step Text Solution:**

1. **Definition and Classification**: Euglenoids are unicellular eukaryotic organisms that belong to the kingdom Protista. This means they are composed of a single cell and have a defined nucleus.

2. **Habitat**: They are primarily found in freshwater environments. This includes ponds, lakes, and other bodies of water where they can thrive.

3. **Cell Structure**: Unlike many other organisms, euglenoids do not have a traditional cell wall. Instead, they possess a flexible protein-rich cell membrane known as the pellicle. This pellicle allows them to change shape and provides structural support.

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