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Head
A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, 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, regardless of size. Heads develop in animals by an evolutionary trend known as cephalization. In bilaterally symmetrical animals, nervous tissue 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. Human 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). Sculptures of human heads are generally based ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Head
In human anatomy, the head is at the top of the human body. It supports the face and is maintained by the skull, which itself encloses the brain. Structure The human head consists of a fleshy outer portion, which surrounds the bony skull. The brain is enclosed within the skull. There are 22 bones in the human head. The head rests on the neck, and the seven cervical vertebrae support it. The human head typically weighs between Over 98% of humans fit into this range. There have been odd incidences where human beings have abnormally small or large heads. The Zika virus was responsible for underdeveloped heads in the early 2000s. The face is the anterior part of the head, containing the eyes, nose, and mouth. On either side of the mouth, the cheeks provide a fleshy border to the oral cavity. The ears sit to either side of the head. Blood supply The head receives blood supply through the internal and external carotid arteries. These supply the area outside of the skull ( e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
