How gaseous exchange takes place in earthworm?

Explanation

**Step-by-Step Solution:**

1. **Introduction to Earthworms**: Earthworms are classified as lower invertebrates and belong to the phylum Annelida. Understanding their classification helps to contextualize their physiological processes.

2. **Absence of Specialized Organs**: Unlike humans, who have specialized organs (like lungs) for respiration, earthworms do not possess any specialized respiratory organs for gaseous exchange.

3. **Mechanism of Gaseous Exchange**: Gaseous exchange in earthworms occurs through their skin, which serves as the primary surface for respiration. This is a key point because it highlights the difference in respiratory mechanisms between earthworms and more complex organisms.

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