The skull has two primary functions: protecting the brain and providing support to the face. The brain is the organ where all of the body's decisions are made and hence its protection is of paramount importance. Eight bones form the cranium that stores our brain. Other bones in our skull form a rigid structure (except for the lower jaw) that is our face. It has sockets for the eyes, which provide a fixed distance between the two eyeballs and hence help in stereoscopic vision. The skull has openings called nasal cavities, which are important for smell, which is used by many animals for food search and predator signaling. There are air passageways that help in inhalation and exhalation of gases. The ears provide us with directional sense. The opening for the mouth provides a passageway for the food to enter our body.
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