Which unicellular organism has irregular shape ?

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for a unicellular organism that has an irregular shape.

2. **Recall Characteristics of Unicellular Organisms**: Unicellular organisms are made up of a single cell and can have various shapes. Some are regular while others can be irregular.

3. **Consider Examples of Unicellular Organisms**: Common examples of unicellular organisms include bacteria, protozoa, and some algae.

4. **Focus on Irregular Shapes**: Among these, we need to identify which organism has an irregular shape.

5. **Identify Amoeba**: The organism that fits this description is **Amoeba**. Amoeba is known for its irregular shape due to its ability to change form.

6. **Explain the Irregular Shape**: The irregular shape of Amoeba is due to its movement mechanism. It uses a crawling type of movement facilitated by the protrusion of its cytoplasm, forming extensions called pseudopodia.

7. **Conclude the Answer**: Therefore, the unicellular organism that has an irregular shape is **Amoeba**.

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