1. The Skeletal System By Tess Grimaldi

2. Function Provides support, movement, and protection Blood cell production Calcium storage Endocrine regulation

3. Structure 206 bones (300-350 at first; fuse together, most have 206 by age 9) Includes bones, tendons, ligaments, and cartilage Separated into two distinctive parts: –Axial skeleton (vertebral column, rib cage, skull) –Appendicular skeleton (pectoral girdles, upper limbs, pelvic girdle, lower limbs)

4. Structure ctd. Periosteum: softer outer covering; provides blood flow to bone; helps bones heal, grow, and fight infection Compact/Cortical bone: hard bone layer. Provides protection. Spongy/Cancellous bone: less dense layer; heals faster than compact bone would Bone marrow: innermost layer. Where blood cells are made

5. Diseases Osteoperosis: bones lose calcium, thin out, can disappear Arthritis: inflammatory, damages joints & surrounding structures Scoliosis: curved spine (“C” or “S” shape) Leukemia/bone cancer: white blood cells multiply uncontrollably; primarily related to blood, but begins in bone marrow. Breaks, fractures, strains, etc. The study of the skeletal system is referred to as orthopedics.