If we look at the turtle meaning, it can be defined as a reptile whose body is encased within a bony shell. Although there are a lot of invertebrate animals and mammals, which have evolved shells, none of them has architecture like a turtle. The top of the shell of the turtle is known as a carapace, and the lower shell is known as a plastron. Both of these are the bony structure and join one another along with each side of the body, which creates a rigid skeleton box. This skeleton box is composed of cartilage and bone and is retained throughout the turtle’s life. The turtles cannot shed the shell or exit from it because it is an integral part of their body. There are almost 365 species of turtle which live on the land and on all of the other continents except Antarctica.