Bones are really amazing. When you grow, they grow, too. When some of your bones are broken, they can grow again. But there is more about bones for us to learn. Here are some interesting facts.
◇Not everyone has 206 bones.
Most books say people have 206 bones, but this is not always true. Babies have more than 300 bones at birth. As they grow, some of their bones join together into one bone later.
◇Some bones make you tall or short.
There is cartilage(软骨)in your joints(关节). The cartilage is compressed(被压缩的) by the gravity(重力) on the earth. So you are shorter after a day's study or work at night. After enough sleep, you will go back as usual in the morning. Astronauts(宇航员) get a little taller in space. This is because there is no gravity.
◇The smallest bones are in the ear.
The ear bones are three small bones. They are the smallest bones in your body. They help sound go into your ears quickly.