skeletdelen

Skeletdelen refers to the bones that comprise the skeleton, together with the connective tissues that support and organize them. In most vertebrates, the skeleton is divided into two major regions: the axial skeleton, which includes the skull, vertebral column, and rib cage, and the appendicular skeleton, which consists of the limbs and the girdles that attach them to the body.

Bones come in several forms. Long bones, such as the femur and humerus, act as levers; flat bones, like many skull bones, protect soft tissues; short bones, such as those in the wrists and ankles, provide stability; and irregular bones, including vertebrae, have complex shapes. Bones are covered by the periosteum and meet at joints via cartilage in articulations.

Bone development occurs mainly through endochondral ossification and intramembranous ossification. Growth in length is driven by growth plates (epiphyseal plates) in children and adolescents, while bone remodeling—driven by osteoblasts and osteoclasts—continues throughout life to maintain strength and mineral balance.

The primary functions of skeletdelen include structural support for the body, protection of vital organs, facilitation of movement in conjunction with muscles, storage of minerals (notably calcium and phosphate), and hematopoiesis in red bone marrow. Bones also participate in endocrine signaling via molecules such as osteocalcin.

Skeletal health depends on nutrition, physical activity, and aging. Common conditions affecting skeletdelen include fractures from trauma and osteoporosis, which reduces bone density and increases fracture risk. Congenital or acquired anomalies can alter bone shape or alignment and influence function.