Final answer:
The primary difference between amphibians and reptiles lies in their skin texture and reproductive methods. Amphibians have moist, permeable skin suitable for cutaneous respiration and typically undergo a two-stage life cycle with aquatic larvae. Reptiles possess dry, scaly skin and lay amniotic eggs, allowing them to live in dry habitats and bypass the aquatic stage.
Step-by-step explanation:
Primary Differences Between Amphibians and Reptiles
The primary difference between amphibians and reptiles is their skin and reproductive adaptations. Amphibians have a moist, permeable skin with mucous glands, which facilitates cutaneous respiration, whereas reptiles have dry, scaly skin, containing keratin and waxy lipids, that minimizes water loss. Reptiles are also amniotes, meaning their embryos are surrounded by protective amniotic membranes, allowing them to lay eggs on land. These eggs are protected by a shell to prevent desiccation. Unlike amphibians, reptiles cannot use their skin for respiration and instead depend solely on their lungs.
Reptiles have been successful in colonizing a variety of terrestrial habitats due to these adaptations. This contrasts with amphibians, which usually require a moist environment or proximity to water, especially for reproduction. Amphibians typically have two distinct life stages, including an aquatic larval stage and an adult stage, whereas reptiles do not go through such dramatic metamorphosis and their young are generally miniature versions of the adults.