All turtles have a shell. Each shell has a top, called a CARAPACE, and a bottom, called a PLAS- TRON. The shell is made up of large, hard scales called SCUTES. Most turtles have 13 scutes on the top shell.

Where are the scutes on a turtle?

A scute or scutum (Latin scutum, plural: scuta "shield") is a bony external plate or scale overlaid with horn, as on the shell of a turtle, the skin of crocodilians, and the feet of birds.

Why do turtles have scutes?

The scutes are plate-like scales similar in composition to the keratin of fingernails. They protect the bones and epithelium of the shell underneath. As the turtle grows, the epithelium produces a new scute beneath the old ones that is a larger diameter than the one layered on top of it, allowing the shell to expand.