What is a sea turtle, and how does it differ from a land turtle?
Like all turtles, sea turtles are reptiles, which means they are cold-blooded vertebrates with scaly skin, lungs and a three-chambered heart. And, like most reptiles, sea turtles lay eggs. The turtle’s upper shell is called the carapace, and the lower shell is called the plastron. The carapace is covered in hard scales called scutes. Sea turtles do not have teeth, but the jaw is a modified beak. There are no visible ears, but sea turtles do have eardrums that are covered by skin. Sea turtles have good vision underwater, but do not see well out of water. Sea turtles differ from terrestrial turtles in several ways. Sea turtles have shells streamlined for swimming, and flippers instead of legs. These adaptations allow sea turtles to move effortlessly through the water. They are strong swimmers and deep divers; green turtles can stay underwater for up to five hours. On the other hand, because the shell is so streamlined, sea turtles cannot retract their heads or flippers to protect themsel
