Why are protozoans placed in Kingdom Protista and not in Kingdom Animalia?

Explanation

**Step-by-Step Solution:**

1. **Definition of Protozoans**: Protozoans are unicellular organisms, meaning they consist of a single cell. They are classified as eukaryotic organisms, which means they possess a nucleus and other membrane-bound organelles.

2. **Nutritional Mode**: Protozoans exhibit a heterotrophic mode of nutrition. This means they cannot synthesize their own food and instead rely on other organisms for nourishment.

3. **Relation to Animals**: Although protozoans share some characteristics with animals, such as motility (movement) and a heterotrophic diet, they are fundamentally different in terms of cellular organization.

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