The following represent an overview of the key concepts of this section:
- Your body is supported by a skeleton.
- The skeleton protects important organs.
- Bones protect important organs. The brain is protected by the skull, eyes are protected by bony sockets and the ribs provide protection for the lungs and heart.
- Most people have 206 bones but some people have an extra pair of ribs (13 pairs). Some people also have extra bones in their thumbs or big toes or may have extra bones at the base of their spine.
- The bones in a baby's head are not fused; they can move slightly. This is why babies can be said to have more bones than an adult. The bones of a baby's skull fuse together at a later stage.
- Joints are where your body bends.
- Bones contain a lot of calcium. This gives the bones rigidity. Without calcium bones and other things like shells tend to get soft.
- Vinegar can remove calcium from eggshells and as a result they go soft.
- It is recommended to eat certain foods that contain calcium in order to keep bones strong and healthy.
- Many bones are not solid but are more like hollow tubes. Tubes can be very strong structures and are often used in engineering design for this reason e.g. tubular legs on chairs.
- Even though bones are strong they can still be broken. The arm bone and the collar-bone are broken more often the thigh bone. This could be because the thigh bone is the largest bone in the body and very strong. The arm bone probably gets broken because when people fall they tend to put out their arms to save themselves. The collar-bone is quite a delicate bone.