The skeletal system is one of the major systems in the body. It contains all the bones and is very important to keep the body from falling apart.
The main jobs that bones do are: provide structure and strength to the body (so you're not a squishy lump); protect the body (the ribs protect the heart); and produce more blood with the marrow.
Muscles are connected to bones with tendons, which are cord-like structures that allow the muscles to move the bones when they contract.
Cartilage is a smooth material between joined bones that stops them from rubbing against each other.
An adult human has 206 bones, all of which are mostly made of calcium.
The femur (or thigh bone) is the longest bone in the human body, and it needs to be that long to support us.
The smallest bone in the human body is the stapes, a bone in the ear.
