Head

Head
The head of a meerkat
Identifiers
TA	A01.1.00.001
FMA	7154
Anatomical terminology []

A head is the part of an organism which usually comprises the eyes, ears, nose and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple animals may not have a head, but many bilaterally symmetric forms do. Heads develop in animals by an evolutionary trend known as cephalization. In bilaterally symmetrical animals, nervous tissues concentrate at the anterior region, forming structures responsible for information processing. Through biological evolution, sense organs and feeding structures also concentrate into the anterior region; these collectively form the head.

The human head is an anatomical unit that consists of the skull, hyoid bone and cervical vertebrae. The term "skull" collectively denotes the mandible (lower jaw bone) and the cranium (upper portion of the skull that houses the brain). The skull can also be described as being composed of the cranium, which encloses the cranial cavity, and the facial skeleton (includes the mandible). There are eight bones in the cranium and fourteen in the facial skeleton.

Sculptures of human heads are generally based on a skeletal structure that consists of a cranium, jawbone, and cheekbone. Though the number of muscles making up the face is generally consistent between sculptures, the shape of the muscles varies widely based on the function, development, and expressions reflected on the faces of the subjects.

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