Animal Skeleton Structure

A skeleton is an internal structure inside an animal's body made of hard pieces called bones. The skeleton does three important jobs. First, it gives the body its shape and helps it stand up. Second, it protects the soft organs inside the body that could be easily hurt. Third, it helps the body move by working with muscles.

Different parts of the skeleton protect different organs. The skull is the hard bone that covers and protects the brain. The rib cage is made of curved bones that protect the heart and lungs like a cage protects a bird. The spine is a long column of small bones down the back that supports the whole body, like a pole holds up a tent.

Different animals have skeletons that match how they move and live. A human skeleton has long leg bones for walking upright on two feet. A bird skeleton has hollow bones that are light so the bird can fly. Birds also have a large, flat breastbone where flight muscles attach. A fish skeleton has a flexible spine and many small bones that help it bend and swim through water.

Interesting Fact: A giraffe has the same number of neck bones as a human—only seven! The difference is that each of a giraffe's neck bones can be over 10 inches long.