HKIN 425 Lecture Notes - Lecture 17: Skeletal Muscle, Collagen, Ossification
Document Summary
Bone: introduction/definitions: vital, dynamic connective tissue, more metabolically active than lean or fat, replace the skeleton every 10 years, adapts structure to function, shape and architecture adapt according to load. Stronger than wood, brick, or concrete: tensile strength = cast iron, 3 x lighter, greater flexibility, elastic up to of breaking strength (fracture limit) Site of blood formation: component of immune system, white blood cells and t cells, calcium and phosphate storehouse. Bone growth: two forms, cortical - shell, trabecular mesh or scaffolding. Length: ossification centers are the sites at which bone deposits at the ends of the shafts shortly after birth (epiphyseal plate, 800 cites; more than one in a bone; coalesce (come together) Proliferating zone multiplication of cartilage cells and elaboration of intercellular ma- trix (therefore increase in length: hypertrophic zone cells arrange in vertical columns with collagen fibres separating the columns (mesh or scaffolding)
