Summary Skeletal system - key notes and cheat sheet

Skeletal System - key notes

Bones & Joints:

- There are 206 bones in a human skeleton.

- One function of a skeleton is to enable the body to move (by using muscles)

- Another function of the skeleton is to protect the organs and nervous system.

- A third function of the skeleton is to support the body (in order for it to keep the body
shape)

- The skull contains bones that fused together after birth to protect the brain.

- The rib cage protects the heart and lungs.

- The vertebrae are bones in the backbone that protects the spinal cord and support
the body.

- There are four types of joints

● Hinge joint
● Ball and socket joint
● Pivot joint
● Fixed

- The shoulder is an example of a ball and socket joint

- The elbow is an example of a hinge joint.

- Bones are hard on the outside and soft in the middle.

- The soft tissue inside bones is called bone marrow.

- The bone marrow in the middle of the bone produces blood cells.

- A Ligament can be stretched a little to allow the joints to be flexible.

- A ligament connects bone to bone.

- The ends of a bone are covered with a smooth substance called cartilage.

- This smooth substance reduces friction between two bones and prevents them from
grinding together.