In spite of these functional differences, the hand and that foot have very similar skeletons. The hand and the foot: As the human species has evolved, the function of the hands and feet has become very differentiated: the hands are used to grasp, while the feet provide stability and mobility for the body.

It extends from the back of the skull to the pelvis and is made of a chain of 33 small bones, the vertebrae, which house the spinal cord and serve as points of attachment for the ribs and muscles. The spine: The spine, also called the vertebral column, is the central axis of the human body. The more numerous bones of the face are irregular in shape and define the cavities of the mouth, the nasal cavities, the eye sockets (orbits) and the sinuses.Īnterior View of skull - Virtual Human Body The head: The skull is not a single bone, but is rather formed of 8 different bones that gradually fuse together during growth. The 4 limbs of the human body contain mainly long bones, to which the motor muscles attach. However, some are quite small, such as the phalanges of the fingers. The long bones, for example, such as the humerus, femur and clavicle, are, as their name implies, long and thin. This classification highlights the match between a bone’s shape and its function. There are generally four types of bones, classified by their appearance: long, flat, irregular and short. The 200 or so bones that form the human skeleton have a variety of shapes. These tissues contain collagen, a protein that gives bones their flexibility, and mineral salts (calcium and phosphorus), which are responsible for their solidity. All bones are composed of groupings of compact and spongy (or cancellous) tissues in different proportions and positions depending on the type of bone. This remarkable strength comes from the nature of the bone tissue. This growth takes place through a process called ossification: cartilaginous cells multiply, die and are replaced by bone cells.Ī bone is 6 times as strong as a bar of steel of the same weight. Bones do not reach their final size until adulthood. The bones of the human body are part of the axial skeleton (the bones of the skull and the face, the vertebrae, the ribs and the sternum) or the appendicular skeleton, formed of the upper and lower limbs and the limb girdles (the bones of the shoulders and the hips) that attach them to the axial skeleton.īone formation starts during the embryonic stage, but many parts of the skeleton are still made of cartilage at birth.

The adult human skeleton contains about 206 bones, but this number can vary slightly from individual to individual: some people, for example, have an extra pair of ribs. The positioning and articulation of the bones of the skeleton also determine the nature of the body’s movements. Like other vertebrates, human beings have an internal skeleton that supports the different muscles in the body and protects the vital organs.

Skull bone names