FUSE | Page 4

Bones Bones provide support for our bodies. Without them we wouldn't be able to stand or walk and although they are very light, they are strong enough to hold our entire weight. Did you know your bones are alive? Although we think of bones as hard, dry objects when we see them in museums, the bones in your body are alive and growing and changing all the time. Cranium Clavicle Humerus Ribs Radius Vertebrae Ulna Pelvis Femur Patella Tibia Fibula Most of your bones are made up of the same materials: periosteum The outer layer of your bones is called periosteum (you say this like pare-ee-OS-tee-um). This is a thin membrane that covers the outside of the bone, that contains blood vessels and nerves. bone marrow In many bones there is bone marrow – this is the inside of the bone that is like a thick jelly and it makes blood cells. cancellous bone compact bone This part of the bone is smooth and hard – in fact it is one of the hardest materials in the body. 4 FUSE Inside the compact bone there are lots of layers of cancellous bone (you say this like KAN-sell-us). This bone looks a bit like a sponge and it isn't as hard as compact bone – but it is still extremely strong.