The adult body is made up of 206 bones. The bones in our bodies help to give the body shape and they also help to protect different organs and systems that are located inside of the body.
Bones are made up of different material, but most bones are made up of the same types of materials.
The Skull | Cranium, Mandible, and Maxilla |
Shoulder girdle | Clavicle and Scapula |
Arm | Humerus, Radius, and Ulna |
Hand | Metacarpals, Phalanges and Carpals |
Chest | Ribs and Sternum |
Spine | Cervical area (top 7 vertebrae), Thoracic (next 12), Lumbar (bottom 5 vertebrae), Sacrum (5 fused or stuck together bones) and Coccyx |
Pelvic girdle | Ilium, Pubis, and Ischium |
Leg | Femur, Tibia, and Fibula |
Ankle | Talus and calcaneus |
Foot | Tarsals, Metatarsals, and Phalanges |
The outside surface of the bone is called the periosteum. This part of the bone helps give the bone nourishment.
It has a thin membrane that has blood vessels and nerves and keeps the bone healthy.
The second layer is called the compact layer, and this is the hard part of the bone with the white color.
This layer is very smooth. Inside of the compact layer is a sponge looking layer called the cancellous.
The spongy part of the bone is made to help keep stress from hurting your bones, helping them not to snap or break in half when you bend or move.
The cancellous is not as hard as the compact bone. The cancellous bone has a job to protect the bone marrow that is located inside of the bone.
This marrow helps to make sure that the blood cells are protected and helps to make blood cells.
Bones change from birth and through adulthood. The baby has around 300 bones when they are born, and these grow together as people get older.
Some baby bones are made up of cartilage which is a soft and flexible material that eventually is replaced by bone.
It is important to try and make sure that you protect your bones as good as you can. Wearing a helmet when skating or riding a bike can help to protect your skull bone.
It is important to protect your skull bone because this bone helps to keep your brain safe.
Bones can be broken by certain types of activities. Broken bones heal but this takes a lot of time and sometimes the bones do not heal back the same way that they were.
Cells inside of your bones help to rebuild the bone, just like skin cells can help to heal you if you get a scratch or a cut.
It is important to make sure to try to keep your bones healthy by drinking milk and eating things that contain calcium, so that your bones stay strong and do not break.
Calcium helps to keep bones strong. The bones are made to store calcium and other minerals and the bones grow for many years and need to be protected.