Consider the following animals :
Fish, Grasshopper, Cockroach, Earthworm, Frog, Cow, Goat, Man, Lizard, Snake
Which of these animals :
breathes only through skin ?

Answer

To determine which of the listed animals breathes only through the skin, we can analyze each animal's respiratory system step by step.

### Step-by-Step Solution:

1. **Fish**: Fish primarily breathe through gills, which extract oxygen from water. They do not breathe through their skin.
- **Hint**: Remember that fish are aquatic animals that use gills for respiration.

2. **Grasshopper**: Grasshoppers breathe through a system of tubes called tracheae, which open to the outside through spiracles. They do not breathe through their skin.
- **Hint**: Grasshoppers have a unique respiratory system that does not involve skin.

3. **Cockroach**: Cockroaches also breathe through tracheae and spiracles, similar to grasshoppers. They do not rely on their skin for respiration.
- **Hint**: Like grasshoppers, cockroaches use tracheae for breathing.

4. **Earthworm**: Earthworms breathe through their skin. Their skin must remain moist for gas exchange to occur effectively. This is a characteristic feature of earthworms.
- **Hint**: Earthworms are known for skin respiration; moisture is essential for this process.

5. **Frog**: Frogs are amphibians and can breathe through both lungs and skin. They do not breathe exclusively through their skin.
- **Hint**: Frogs have dual respiration methods: lungs and skin.

6. **Cow**: Cows breathe through lungs. They do not use their skin for respiration.
- **Hint**: Cows are terrestrial mammals that rely on lungs.

7. **Goat**: Similar to cows, goats also breathe through lungs and do not use their skin for respiration.
- **Hint**: Goats are also terrestrial mammals with lung respiration.

8. **Man**: Humans breathe through lungs and do not breathe through their skin.
- **Hint**: Humans are terrestrial and rely solely on lungs for breathing.

9. **Lizard**: Lizards breathe through lungs and do not use their skin for respiration.
- **Hint**: Lizards are reptiles that have lungs for respiration.

10. **Snake**: Snakes also breathe through lungs and do not breathe through their skin.
- **Hint**: Snakes, like lizards, have a lung-based respiratory system.

### Conclusion:
After analyzing all the animals, the only one that breathes exclusively through its skin is the **earthworm**.

### Final Answer:
**Earthworm** is the animal that breathes only through its skin.

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