The excretory organs in round worm are________.

Explanation

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about the excretory organs in round worms, which belong to the phylum Nematoda.

2. **Understand the Excretory System**: In nematodes (round worms), the excretory system is specialized for the removal of waste products.

3. **Recognize the Excretory Organs**: The primary excretory organs in round worms are known as flame cells. These cells are responsible for collecting and excreting waste.

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