Skeletal System

Parts of the skeletal system Bone Cartilage Cover bones, between bones Ligaments Hold 2 or more bones together

Functions of the skeletal system Support Against gravity Protect internal organs Brain, heart, lungs Provide for movement Attached muscles move bones Store minerals Especially calcium Blood cell formation In bone marrow

Parts of skeleton Axial skeleton Appendicular skeleton Skull, ribcage, vertebral column Appendicular skeleton Pelvis, arms, legs, hands, feet, shoulder

Bone structure Periosteum Tough covering on outside Compact bone Very dense, in shaft of long bones Spongy bone Cushioning part, at ends of long bones Haversian canals Place fpr blood vessels to pass Osteocytes (bone cells) Osteblasts - build bone Osteoclasts - break down bone Bone marrow Blood cell formation Matrix Fills up the space beweeen osteocytes Made of calcium (strength), collagen (flexibile)

Joints Where two or more bones come together Types Immovable Skull bones Slightly movable Vertebrae, pelvis Freely movable Ball and socket - shoulder Pivot - neck Hinge - knee Saddle - wrist

Joint structure Freely movable joints Ends of bones are covered by cartilage Keeps bone from grinding away on each other Ligaments Hold bones together Synovial fluid Produced by cells in the joint Lubricates the bones so they can slide past each other

Skeletal system disorders Arthritis Inflammation of a joint Osteoporosis Brittle bones Results from loss of calcium Breaks These heal in a series of steps