In which one of the following animals is respiration done by skin ?

Respiration in animals occurs through various mechanisms depending on their habitat and biological complexity. Frogs, which are amphibians, exhibit a unique ability to respire through their skin, a process known as cutaneous respiration [c4][t1]. While adult frogs possess lungs for breathing on land, they rely heavily on their moist, porous skin for gas exchange when submerged in water or in humid environments [c4][t2][t5]. This cutaneous exchange can account for more than 50 percent of an amphibian's oxygen intake [t8]. In contrast, flying fish and sea horses are bony fish that primarily use gills (branchial respiration) to extract oxygen from water [t7]. Chameleons are reptiles that possess dry, scaly skin to prevent desiccation and rely almost exclusively on lungs for breathing [t10]. Therefore, among the given options, the frog is the animal that utilizes its skin for respiration.

Sources

1. [1] Science-Class VII . NCERT(Revised ed 2025) > Chapter 9: Life Processes in Animals > 9.2.2 Do other animals breathe the same way as humans do? > p. 133
2. [2] https://en.wikipedia.org/wiki/Fish_gill