Skeletal System

Functions of the Skeletal System THINK! – What are the four levels of organization? Cells, Tissues, Organs, Organ Systems Provides shape & support (206 bones) Allows for body movement with its 26 vertebrae in the backbone Protects the internal organs Produces blood cells Stores certain materials like calcium and phosphorus

Activity: Turn to your partner and Label the Human Skeleton

Joints of the Skeleton Brain Pop: How Joints Work! Places in the body where two bones meet Immovable Joints allows no movement bones of skull & ribs to sternum

Joints of Skeleton Ball & Socket Joint allows the greatest range of motion Shoulder & Hip

Joints of Skeleton Pivot Joint Allows one bone to rotate around another Neck, arm (radius)

Joints of Skeleton Hinge Joint Allows forward & backward motion Knee, Elbow, Phalanges, Mandible

Joints of Skeleton Gliding Joint allows one bone to slide over another allows bend and flex as well as limited side-to-side motion Wrist, ankles, vertebrae THINK! – What connective tissue connects bone to bone? Ligaments

Bone Growth THINK! – Take a look at the picture to the right. How do you think a child’s bones grow over time? Cartilage is replaced slowly by bone as solid tissue grows outward. Over time, the bone reshapes to include blood vessels, nerves, and marrow. Osteoblasts are bone forming cells Osteoclasts are cells which break down bone releasing calcium into the bloodstream

Structure of Bone Brain Pop: Bone Structure

Structure of Bone Periosteum – membrane that covers all of the bone except ends Compact bone – found underneath membrane Hard and dense but not solid Canals carry blood vessels and nerves from bone’s surface to living bone cells. Spongy bone - inside compact bone and at ends Marrow (contained in bone spaces) Red - produces body’s blood cells Yellow – stores fat that serves as an energy reserve