Luurankoosasto

Luurankoosasto, known in English as the skeletal system or skeleton, is the body's internal framework. It provides structural support, allows for movement, protects vital organs, produces blood cells, and stores minerals like calcium and phosphorus. In adult humans, the skeleton typically consists of 206 bones, though this number can vary slightly due to factors like fused bones. The skeletal system is divided into two main parts: the axial skeleton, which includes the skull, vertebral column, and rib cage, and the appendicular skeleton, which comprises the bones of the limbs and their girdles (shoulder and pelvic). Bones are living tissues that constantly remodel themselves. They are composed of bone tissue, cartilage, and connective tissue. The surface of bones is covered by a membrane called the periosteum, which contains nerves and blood vessels. Within the bones are cavities that house bone marrow, responsible for producing red blood cells, white blood cells, and platelets. Joints, where two or more bones meet, allow for a range of motion and are often cushioned by cartilage and lubricated by synovial fluid. The skeletal system is crucial for overall health and function.