Introduction
The human skeleton is the internal framework of the body. It is composed of 270 bones at birth – this total decreases to 206 bones by adulthood after some bones have fused together.[1] The bone mass in the skeleton reaches maximum density around age 30. The human skeleton can be divided into the axial skeleton and the appendicular skeleton. The axial skeleton is formed by the vertebral column, the rib cage and the skull. The appendicular skeleton, which is attached to the axial skeleton, is formed by the pectoral girdle, the pelvic girdle and the bones of the upper and lower limbs.
The human skeleton serves six major functions; support, movement, protection, production of blood cells, storage of ions and endocrine regulation.
The human skeleton is not as sexually dimorphic as that of many other primate species, but subtle differences between sexes in the morphology of the skull, dentition, long bones, and pelves exist. In general, female skeletal elements tend to be smaller and less robust than corresponding male elements within a given population. The human female pelvis is also different from that of males in order to facilitate child birth.[citation needed] Unlike most other primates, human males do not have penile bones.
Process
The adult human skeletal system consists of 206 bones, as well as a network of tendons, ligaments and cartilage that connects them. The skeletal system performs vital functions — support, movement, protection, blood cell production, calcium storage and endocrine regulation — that enable us to move through our daily lives.
Animals with internal skeletons made of bone, called vertebrates, are actually the minority, as 98 percent of all animals are invertebrates, meaning they do not have internal skeletons or backbones. Human infants are born with 300 to 350 bones, some of which fuse together as the body develops. By the time most children reach the age of 9 they have 206 bones.
Evaluation
Label the missing parts of skeletal system
Conclusion
Credits
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