Jim, Tyler and Matt

Adult Bones

Adult humans have 206 bonesAccounts for ~12-15% of body mass

Some areas have a higher concentration of bones than others:54 bones in wrists, palms and fingers52 bones in ankles and toes14 facial bones1 throat bone (hyoid)

More than half the bones of the body are in the hands and feet

Adult Bones

Found throughout bodyWithin softer bodily tissues

Variety of sizes, shapes and functionsInner ear bones vs. femur

Provides framework of body 2 divisions of bone

Axial skeletonAppendicular skeleton

Axial Skeleton

80 bones

Skull Vertebral column Ribs

Maintains upright posture of human body

Protects vital organs

Appendicular Skeleton 126 bones

Shoulder girdles Upper limbs Pelvic girdle Lower limbs

Makes movement possible

Protects major organs of digestion, excretion and reproduction

Types of Bone

Long bonesLength>diameter

Short bonesLength similar to width,

depth and diameter

Flat bones Irregular bones

Complicated shapes

Sesamoid bones

Movement of the Body

Bones and muscles work together to allow the body to move

Various shapes and sizes of bone create different movement

JointsWhere 2 or more bones come together

Joints of the Body Pivot

Rotation Ball and Socket

Almost all planes Hinge

Flexion and extension Ellipsoid

Flexion, extension, adduction, abduction and circumduction

Saddle Flexion, extension, adduction,

abduction and circumduction Gliding

Structure of Bone

Consists of two main componentsOrganic- produced as a result of the bodyInorganic- “bone mineral”

The combination creates both the strength and flexibility of bone

Organic Component of Bone

Primarily collagenProteinTriple helix= tensile strengthAbout 90-95% of organic component

Other 5-10% is a homogenous liquid called ground substanceMixture of water and proteinsSimilar to an extracellular matrix, but for the

fibers

Inorganic Component of Bone

Primarily formed from salts of calcium and phosphateMajor salt is hydroxyapatite (Ca10(PO4)6(OH)2)

Other trace mineralsMagnesiumSodiumPotassiumCarbonate

Provides compressional strength of bone

Chemical Composition of Bone

The exact percentages depend on a variety of factors:Age, gender, ethnicity, health status and bone site