anatomy bones and bone tissue Flashcards
hematopoiesis
blood cell formation
number of bones in the body
206
5 types of bones
long bones, short bones, flat bones, irregular bones, sesamoid bones
long bone definition
greater length than its width
short bone definition
width is roughly same as height
flat bone definition
broad, flat, and thin - 2 layers of contact bone squishing a layer of spongey bone in between
irregular bone definition
typically irregularly shaped, lots of bumps and protuberances ex: vertebrae, ethmoid bone
sesamoid bone definition
“resembling a sesame seed” develop in tendons
largest sesamoid bone
patella (kneecap)
spongey bone also known as
trabecular (little beans) /cancellous bone (lattice)
compact bone also known as
cortical bone (derived from cortex - latin for bark)
what is the periosteum
living membrane surrounding the bone
hyaline cartilage
articulating surface - allows for bones to articulate but not grind against each other
diaphysis
shaft of a long bone
what are the sharpies fibres (perforating)
interlace between the membrane and the boney tissue
epiphysis
proximal and distal ends of a long bone
red bone marrow
found in the epiphysis, within spongey bone pockets
yellow bone marrow
found in the diaphysis of a long bone, within compact bone medullary cavity
nutrient foramen
for an artery vein can exit or enter the medular canal
endosteum
membrane that lines the medullary cavity
how many bones do newborns have
a newborn has more bones than an adult.
the diaphysis is separated from the epiphyses
what are the epiphyseal plates
growth plates when forming, metaphysis after bones have been connected.
located at the point between the epiphyses and diaphysis
what can happen if the epiphyseal plates are damaged
can impact growth, ex: causing one leg to stop growing at a particular length and the other to grow normally resulting in one short leg and one “normal” length leg
what do the epiphyseal plates
allow for growth of bones linearly
Diploe (e with dot above)
spongey bone when found in between 2 layers of contact bone of the skull
where is sponge bone found in the long bone?
epiphyses
what does the microscopic structure of bone tissue contain
extracellular matrix (ECM), which is made up of inorganic and organic matrixes
where is compact bone found in the long bone?
diaphysis
Extracellular matrix
made up of organic and inorganic matrixs
(substances)
inorganic matrix
minerals - make up the majority of the composition of bones. 65% of every bone is made up of minerals, 65% of bones total weight
organic matrix
sometimes referred to as osteoid.
consists of collagen fibres, protein fibres, proteoglycans (bone specific proteins)
remaining 35% of bone is made up of organic matter
what is the osmotic gradient?
holds organic matrix (osteoid) and inorganic matrix together
what are hydroxyapatite crystals
what gives bone its hardness - combination of the calcium and phosphorus inorganic matters
basic functional unit of compact bone
osteon
what happens if you remove the organic matrix from bones
results in brittle bones - shatters easily
what happens if you remove the inorganic matrix from bones
results in bendable bones - cannot resist compression
where do osteocytes reside in compact bone
lacunae
osteoblasts
younger cells, bone producing (building) cells
osteoclasts
bone reabsorbing cells - with H+ and enzyme secretion
5 Compact bone structures
Osteons, lamellae, central canal, lacunae, canaliculi
osteocytes
osteo - bone
cytes - cells
cells maintaing homeostatis (mature cells)
traps osteoblasts and transforms them into osteocytes to maintain ECM
series of circular boney tissue in opposing directions of compact bone
lamellae
canals that extend between lacunae allowing for communication
canaliculi
allows for appositional growth
circumferential lamellae
interstitial lamellae
in between adjacent osteons (used to be osteons, but have remodelled)
