1. Divisions of the skeletal system
Bones – humans have 206 bones
80 in the axial skeleton : skull, ear bones, hyoid bone in neck, ribs, sternum and vertebrae

2. Divisions of skeleton
126 in the appendicular skeleton: bones of upper and lower limbs, and bone groups called girdles that connect limbs to the axial skeleton.
(See p. 126)

3. Bone surface markings:
1. Depresssions and Openings:
A. Foramen (fo-RA-men) – opening for blood vessels, nerves or ligaments
Ex. Holes in sacrum

4. More depressions and openings
B. Meatus – a tube-like channel within a bone
Ex. Hole for ear in skull
C. Fossa – a shallow depression in or on a bone
Ex. Dip where mandible attaches to skull

5. More Bone surface markings:
2. Processes that form joints:
A. Condyle – a large, rounded prominence that forms a joint
Ex. Knobs on lower femur at knee

6. 2. Processes that form joints continued:
B. Head – rounded projection that is supported on a thinner “neck” and forms a joint
Ex. Top of femur – “Ball”
C. Facet – smooth, flat articular surface
Ex. Where vertebrae come together

7. 3. Processes to which tendons, ligaments and other connective tissues attach:
A. Tuberosity – large, rounded projection, usually with a rough surface
Ex. deltoid tuberosity of the humerus – on the side in middle of the bone

8. B. Spinous process or spine – a sharp, slender projection
More processes
B. Spinous process or spine – a sharp, slender projection
Ex. Part on vertebrae that you feel as someone’s spine
C. Trochanter – large, blunt projection only on the femur – other bulge at the top, not the ball part.

9. D. Crest – prominent border or ridge
More processes
D. Crest – prominent border or ridge
Ex. iliac crest of top of hip bone