1. Functions of Skeletal System
1.1. Support
1.1.1. Provide a scaffold to support the body's weight
1.2. Movement
1.2.1. Serve as points of attachment for muscles
1.3. Protection
1.3.1. Protect internal organs by covering/surrounding them
1.4. Mineral Storage
1.4.1. Bones store calcium and phosph
1.5. Blood Cell Production
1.5.1. Bone marrow is reponsible for producing blood cells
1.6. Energy Storage
1.6.1. Yellow bone marrow stores fat, which works as energy reserve
2. Bone Classification
2.1. Long Bones
2.1.1. Cylindrical in shap, longer than wide
2.1.2. Found in arms and legs
2.1.3. Function as levers, move when muscles contract
2.2. Short Bones
2.2.1. Cube-like in shape, approx equal in length, width, and thickness
2.2.2. Found in carpals of wrists and tarsals of ankles
2.2.3. Provide stability and support & limited motion
2.3. Flat Bones
2.3.1. Thin and curved
2.3.2. Cranial bones, scapulae, and sternum
2.3.3. Points of attachment for muscles and protect organs
2.4. Irregular Bones
2.4.1. Not easily characterized and doesnt fit other classifications
2.4.2. Vertebrae and facial bones
2.4.3. Protect from compressive forces
2.5. Sesamoid Bones
2.5.1. Small and round, embedded in tendons
2.5.2. Patellae
2.5.3. Protect tendons from compressive forces
3. Bone Cells and Tissue
3.1. Bone Cells
3.1.1. Osteoblasts
3.1.1.1. forms bone matrix
3.1.2. Osteocytes
3.1.2.1. maintain bone tissue
3.1.3. Osteogenic Cells
3.1.3.1. stem cell
3.1.4. Osteoclasts
3.1.4.1. resorbs bone
3.2. Compact Bone
3.2.1. Denser,stronger type of bone tissue
3.2.2. Found under periosteum and disphyses of long bones
3.3. Spongy Bone
3.3.1. contains osteocytes housed in lacunae,found in a lattice-like network of matrix spikes called trabeculae
4. Bone Formation and development
4.1. Bone remodeling
4.1.1. resorption of old/damaged bone where osteoblasts lay new bone to replace resorbed bone
4.2. Intramembranous Ossification
4.2.1. Compact and spongy bone develop from sheets of mesechymal connective tissue
4.3. Endochronal Ossification
4.3.1. Bone develops by replacing hyaline cartilage
4.4. How bones grow in length
4.4.1. Reserve Zone
4.4.1.1. Matrix Production
4.4.2. Proliferative Zone
4.4.2.1. Mitosis
4.4.3. Maturation and hypertrophy Zone
4.4.3.1. Older and larger than those in proliferative zone
4.4.4. Zone of Calcified Matrix
4.4.4.1. Zone closest to diaphysis
4.4.4.2. Dead because matrix around them has calcified
4.5. How bones grow in diameter
4.5.1. osteoclasts resorv old bone and produce new bone tissue near periosteum
5. Bone Repair
5.1. Fractures
5.1.1. Closed
5.1.1.1. Fracture in which skin remains intact
5.1.2. Open
5.1.2.1. A fracture in which at least one end of the broken bone tears through the skin - high risk of infection
5.1.3. Transverse
5.1.3.1. Occurs straight across long axis of bone
5.1.4. Oblique
5.1.4.1. Occurs at an angle not 90 degrees
5.1.5. Spiral
5.1.5.1. Bone segments are pulled apart as a result of twisting motion
5.1.6. Communicated
5.1.6.1. several breaks result in many small pcs between two large segments
5.1.7. Impacted
5.1.7.1. One fragment is driven into the other
5.1.7.1.1. usually result of compression
5.1.8. Greenstick
5.1.8.1. Partial fracture in which only one side of bone is broken
5.2. Fracture hematoma
5.2.1. Whena bon breaks, blood flows from any vessel torn by fracture, blood begins to clot and after about 6-8 hours forms this
5.3. Internal Callus
5.3.1. Chrondrocytes from endosteium
5.4. External Callus
5.4.1. Periosteal chondrocytes and osteoblasts
5.4.2. Hyaline Cartilage and one
5.4.3. Stabilizes fracture