Amphibians and reptiles have different skin characteristics, best suited to their habitat, and only the reptiles have bumpy (or scaly skin). Amphibians live both in water and on land, unlike reptiles, who live only on land. The amphibians have soft, slippery and non-scaly skin allowing them easy escape from predators (who cannot get a good grip due to lack of friction). This type of skin is also water-permeable, and allows them to obtain moisture from land (from underground burrows, etc.) during dry season. Reptiles, on the other hand, have dry and scaly skin, which prevents loss of moisture from skin. The outer layer is composed of keratin and is called the epidermis, while the underlying dermis is the real skin (composed of connecting tissues).
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