endoskeleton

An endoskeleton is a skeleton that is on the inside of an animal's body. It is made up of bones and cartilage, and it helps to support the animal's body and protect its organs.

Endoskeletons are found in many different animals, including humans, fish, birds, and reptiles. They are different shapes and sizes depending on the animal. For example, the endoskeleton of a human is made up of 206 bones, while the endoskeleton of a fish is made up of many small bones that are fused together.

Endoskeletons are important for many reasons. They help to support the animal's body and protect its organs. They also help the animal to move. For example, the bones in the human skeleton work together to allow us to walk, run, and jump.

The endoskeleton of a fish is made up of bone.