Question

Give scientific reason.

Though tortoise lives on land as well as in water, it cannot be included in class-Amphibia.

Answer 1

1. Tortoises that live on land use their lungs to breathe. 
2. When in water, it extends its nares (nasal apertures) and breathes air.
3. It cannot absorb oxygen dissolved in water. In both habitats, it breathes through its lungs.
4. This is not the case with real amphibians, however. They can breathe in water through their skin and out on land via their lungs.
5. Tortoises also have an exoskeleton, which is absent in Amphibia. As a result, the tortoise cannot be classified as an amphibian.