Seriously Skeletal System

1. Seriously Skeletal System

2. System Anatomy • Bones – 206 (axial and appendicular) • Joints - articulations • Cartilage – connective tissue • Ligaments – connect bone to bone

3. System Physiology • Support body and form internal framework • Protect soft body organs (i.e. skull) • Movement – skeletal muscles use bones as levers to move body • Storage – fat, minerals (calcium/phosphorus) • Blood Cell Formation – happens in marrow of certain bones

4. Bone Classification • Long Bones – longer than they are wide • i.e. humerus, femur

5. Bone Classification • Short Bones – cube shaped containing spongy bone • i.e. bones of wrists and ankles

6. Bone Classification • Flat Bones – thin, flattened and usually curved • Skull, ribs, sternum

7. Bone Classification • Irregular Bones – bones that don’t fit in any other category • i.e. vertebrae, hip bones

8. Bone Markings • Projections – sites of muscle, tendon and ligament attachment • Depressions – sites that allow blood vessels and nerves to pass; can be articular surface

9. Projections/Processes (bumps) • Tuberosity: large rounded projection • Crest: Narrow ridge of bone • Spine: Sharp, slender, pointed projection

10. Depressions/Cavities • Meatus: Canal-like passageway • Fossa: Shallow depression in a bone • Foramen: Round or oval opening through bone

11. Long Bone Epiphysis – end of long bones, filled with spongy tissue. • Diaphysis (shaft) – makes up most of the bones length, composed of compact bone. • Periosteum – fibrous connective tissue membrane. It protects the diaphysis. • Cartilage – prevents friction between bones • Spongy bone – small needle-like pieces of bone and lots of openings.

12. Marrow • Yellow marrow – adult – stores fat • Red marrow – infant – makes blood cells • Compact bone – dense and looks smooth and homogeneous. • Medullary Cavity – storage area for fat

16. Microscopic Bone Anatomy • Osteocyte: mature bone cell • Lacunae: tiny cavity surrounding bone cell • Lamellae: concentric circles • Canaliculi: tiny canals that transport nutrients to each bone cell

17. Microscopic anatomy (cont.) • Central Haversian Canal: carries blood vessels and nerves to all areas of bone • Osteon: Canal + Matrix rings (the whole thing)

19. Articulations • Where bones meet • All bones meet with at least one other bone except the hyoid bone, which holds your tongue in place.

20. Structural- what is made out of? Fibrous tissue Functional- What does it do? Bones are immovablefor best protection Example - skull sutures (stitches) that hold the skull bones together. Types of ArticulationsA. Synarthrosis

21. Structural (what it is made out of.) Cartilaginous (cartilage) Functional Holds bones together, But they are slightly movable Example: vertebrae to vertebrae Articulations ContinuedB. Amphiarthrosis

22. Structural Filled with Synovial fluid (fluid-cavity) Function: Makes a freely movable joint. -Examples - ball and socket and hinge joints of hip, shoulder, elbow Classification of ArticulationsC. Diarthrosis