Reptiles

Reptiles are often thought of as slimy, but their skin their skin is actually cool, dry, and leathery. The scales, which give the reptiles' skin their texture, are part of a thick skin with few glands. The reptile must periodically shed its outgrown scales and replace then with a larger set, which the reptile grows before it sheds the old. Their thick skin helps them conserve some heat in its body. Many sun themselves to …

…have a three-chambered heart with a partial wall inside the main chamber. This means that less mixing of oxygen-filled blood and carbon dioxide-filled blood occurs than in amphibians. This type of circulatory system provides more oxygen to all the parts of the body. Reptiles are important predators in many environments. In farming areas, snakes eat rats and mice that destroy grains. Small lizards eat insects, and large lizards eat small animals that are considered pests.