Question

Fish and frog can respire in water. Can they respire
through their skin? If yes, why do they have gills?​

Answer 1

$\huge\underline{\underline\mathtt{Answer:-}}$

Fishes cannot respire by skin, they can respire in water only by gills as they are primarily aquatic.

Frogs are amphibians, so they are primarily adapted to land and secondarily adapted to water. Hence when on land they respire by lungs and when in water they respire by skin (autaneous) respiration, and more over water is needed by amphibians only for external fertilisation.