What is the characteristic of amphibian skin?

Explanation

### Step-by-Step Text Solution:

1. **Classification of Amphibians**: Amphibians belong to the class Amphibia, which is part of the division Vertebrata. This class includes approximately 3000 species that are adapted to live both on land and in water.

2. **Skin Characteristics**: The skin of amphibians has several distinctive features:
- **Soft and Moist**: Amphibian skin is soft and moist due to the presence of mucous glands located beneath the skin. These glands secrete mucus, which helps keep the skin hydrated.
- **Lack of Scales**: Unlike many other vertebrates, amphibians do not have scales on their skin. Instead, their skin can be described as rough and smooth at the same time.
- **Respiratory Function**: Amphibian skin plays a crucial role in respiration. Adult amphibians, such as frogs, can respire through their skin as well as through their lungs. This is particularly important for gas exchange, especially when they are in water.
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