Human Skeletal System

Human Skeletal System

Human skeleton is the internal framework of the body. It is composed of 270 bones at birth ^[1][2][3] – this total decreases to 206 bones by adulthood after some bones have fused together. The  bone mass in the skeleton reaches maximum density around age 30. The human skeleton can be divided into the axial skeleton and  the append circular skeleton. The axial skeleton is formed by the vertebral column, the rib cage and the skull. The append circular skeleton, which is attached to the axial skeleton, is formed by the pectoral girdles, 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 pelvis exist. In general, female skeletal elements tend to be smaller and less robust than corresponding male elements within a given population. The pelvis in female skeletons is also different from that of males in order to facilitate child birth.

The skeleton serves six major functions; support, movement, protection, production of blood cells, storage of minerals and endocrine regulation.

The joints between bones allow movement, some allowing a wider range of movement than others, e.g. the ball and socket joint allows a greater range of movement than the pivot joint at the neck. Movement is powered by skeletal muscles, which are attached to the skeleton at various sites on bones. Muscles, bones, and joints provide the principal mechanics for movement, all coordinated by the nervous system.