Bones Flashcards
describe the structure of cartilage
semirigid, avascular form of connective tissue
what is the function of costal cartilages
attach the ribs to the sternum
how does cartilage receive nourishment and why
Cartilage is avascular, therefore nourished by diffusion
how do bones form from cartilage
cells incartilaginous growth plates continue to proliferate, increasing the length of the bones concerned until they eventually ossify, when growth ceases
a) what do hyaline, elastic and fibrocartilage contain
b) where are they found
hyalin- collagen, articular surfaces of bones
elastic- collagen+elastic, ear
fibrocartilage- collagen+little cell+ground substance, intervertebral discus
where do osteoblasts originate from and what do they become
originate from osteochondral progenitor cells and become osteocytes and connect
where are osteocytes located and how do they connect
located in lacunae, connected one another through canaliculi
what does bone matrix contain
inorganic- hydroxyapatite, composed mostly of calcium and phosphorus organic component of bone is type I collagen
what gives the hardness of bones
Relation of minerals with collagen fibers
what is periosteum and endosteum
periosteum- fibrous connective tissue covering that surrounds bone except joints
Endosteum- covering the internal surface
what are the layers of periosteum
- fibrous layer (outer). thin, dense connective tissue containing fibroblasts
- Osteogenic (inner)- conatins osteogenic cells, richly supplied with blood, lymph vessels and nerves
types of bone
compact (superficial thin layer around central mass of spongy bones) and spongy (trabecular or cancellous)
what do flat bones and diploe consist of
two compact bone plates seperated by spongy bone layer
contains diploic veins that course parallel through the diploe
what are most of the nerves passing through the internal cavity with nutrientartery
vasomotor fibers that regulate the blood flow
describe the axial and appendicular skeleton
- axial skeleton- bones of head, neck (cervical vertebrae) and trunk (ribs, sternum, vertebrae, sacrum)
- Appendicular skeleton- bones of limbs—pectoral (shoulder) and pelvic girdles
