Question

Give scientific reasons.

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

Answer 1

• When tortoise lives on the land, it respires with the help of lungs.
• When in water, it puts out its nares (nasal openings) out of the water and breathes air.
• It cannot take up oxygen dissolved in water. In both the habitats it respires with the help of lungs. In case of true amphibians, this is not the case.
• They can breathe in water with the help of skin and on land with the help of lungs.
• Tortoise also has exo-skeleton which is lacking in Amphibia. Therefore, tortoise cannot be included in class Amphibia.