Their heads are lizard-like, with a hooked beak and toothless jaw. Their bodies are enclosed in shell for protection. The top half of the shell is called the carapace. It feels smooth and is grey, green, brown and black. It's tougher than the under shell, which is called the plastron and is yellowish white.
Males have a larger tail than females.
The female Green Sea Turtle leaves the sea only to give birth. Afterwards she scrapes the sand back to cover the eggs, then she goes back into the sea. About two months later the eggs hatch and the young turtles head straight for sea. Somehow they know that they must live in the water and not on land. This is called instinct.