Bones & Joints

The human skeleton has 206 bones. Our bones begin to develop before birth. When the first form of the bone, it is made of flexible cartilage, but within a few weeks it begins the process of ossification (pronounced: ah-suh-fuh-kay-shun). Ossification when cartilage is replaced by hard deposits of calcium phosphate and stretchy collagen, the main components of bone. Takes about 20 years for this process is completed.

Bones of children and young teens are smaller than adults and contain "the development" called growth plates. These plates include the columns of cartilage cells that develop long, and then change into hard bone mineral. These plates are easy to spot growth on a X-ray. Because girls mature earlier at age boys, change your plates to the development of hard bone age before.

Every time you sprint through the halls because you're late for class, score against your opponent in a game, or shoot a swimming pool with friends, you're using bones, your muscles, and joints. Without these important body parts, you agree to be serious - you can not sit, stand, walk, or any of your activities each day.

From the top of our toes to us, our bones provide support for our bodies and help form our shape. Skull protects the brain and forms the shape of our face. The spine, a path for messages between the brain and body, are protected by the backbone, or spine. The ribs form a cage that shelters the heart, lungs, liver, and spleen, and the pelvis helps protect the bladder, bowel, and girls, the reproductive organs. Although we are very light, bones are strong enough to support all our weight.

Joints occur where two bones meet. They make the skeleton flexible - without them, movement would not be. Muscle is necessary for movement: They're the tough elastic tissue volume, which pull our bones when we move.

Together, the bones, our muscles and joints - along with tendons, ligaments and cartilage - form our musculoskeletal systems and enable us to I do physical activity every day.