The skull the skull protects the most important part of all: the brain. You may notice the skull pressing you the head, especially in the back, a few centimeters (or inches) above the neck. Skull, is in fact composed of different bones. Some of these bones protect the brain, while others make up the structure of the face. If you play under the eyes, you can feel the ridge of bones that they are the holes where the eyes are housed. And, although you can not see it, the smallest bone in the body is also found in the head. The stirrup, located behind the eardrum, measures only 2.5 to 3, 3 mm (or 0.13 to 0.1 inches)! Do you want to know something more? The only bone of the head which you can move is the lower jaw.
It opens and closes to allow you to speak and chew food. The skull is great, but much has changed since you were a baby. All babies are born with spaces between the bones of the skull. This allows the bones to move, closing and overlap while the baby passes through the birth canal. Little by little, as the baby grows, the space between the bones closing down until it disappears completely, and the bones of the skull are interconnected by means of special joints called sutures. Hands when using the computer keyboard, you bounce on a swing, and even when you take lunch, use the bones of the fingers, hands, wrists and arms. Each arm It is attached to a shoulder blade or scapula, a large, triangular bone at the top and rear corner on both sides of the rib cage. The arm consists of three bones: the humerus, which is above the elbow, the RADIUS and ulna, which are below the elbow. Each of these bones is wider at the ends and more thin or narrow in the middle part, which helps to strengthen the points where established contact with other bones.