The skeleton forms the frame for the body and makes up about 1/5th of the body's weight. It is made up of 206 bones. It also includes cartilage, joints, and ligaments. Besides for forming our body frame the skeleton has several other jobs. It is the anchor and support for all our muscles and even our organs. It protects our vital organs like our brain, spinal cord, heart and lungs. It allows us to move with muscles attached by tendons using the bones as levers. It is a place for our body to store fat and minerals, like calcium. It is where the body makes most of its new blood cells. Bones come in many shapes and sizes. The long bones have a long shaft and two bigger ends. These include the bones of the arms and legs. The largest bone in the body, the femur, is a long bone. It is 2 feet long and hollow to make it lighter. It is very strong to support the body's weight. The short bones are cube-shaped and include the bones of the wrist (carpals) and ankle (tarsals). The flat bones are thin, curved and flattened like the sternum and skull. Lastly, there are irregular bones like the vertebra and pelvis. Each section of the skeleton has a job. Below see all the parts of the skeleton and how they work together to make the body a strong, moving machine.
NGSS Life Science Progression K-12
LS1.A Structure and Function
K-2 All organisms have external parts that they use to perform daily functions.
3-5 Organisms have both internal and external macroscopic structures that allow for growth, survival, behavior, and reproduction.
6-8 All living things are made up of cells. In organisms, cells work together to form
tissues and organs that are specialized for particular body functions.
9-12 Systems of specialized cells within organisms help perform essential functions of life. Any one system in an organism is made up of numerous parts. Feedback mechanisms maintain an organism’s internal conditions within certain limits and mediate behaviors.