1, bone pinyin: gǔtou.

2, bone bone tissue is composed of a mixture of living cells and minerals (mainly calcium and phosphorus), and it is these minerals that give bones their solidity.

3, Bones come in different shapes and sizes, for example, arm bones are long bones, wrist bones are short bones, sternum and skull bones are flat bones, and vertebrae are irregular bones. Adult bone is composed of two main types of tissue: hard dense bone on the outside and porous cancellous bone, also known as spongy bone, on the inside. The thigh bone, or femur, of the long bones is filled with fat called yellow marrow in the center.