*Human skeleton
- *Total bones*: 206 bones in adults, 270 at birth
- *Divisions*:
1. *Axial skeleton* 80 bones - skull 22, vertebral column 26, ribs/sternum 25, hyoid 1
2. *Appendicular skeleton* 126 bones - limbs 64, shoulder girdle 4, pelvic girdle 2
- *Largest bone*: Femur/thigh bone ∼45-48cm
- *Smallest bone*: Stapes in middle ear ∼2.5-3mm
- *Bone types*: Long, short, flat, irregular, sesamoid
- *Composition*: 60-70% inorganic minerals mainly calcium phosphate, 30-40% organic collagen + water
- *Functions*: Support, protection, movement via joints, blood cell production in marrow, mineral storage
- *Joints*: ∼360 joints total. Types: fibrous, cartilaginous,