week 3 bones Flashcards
clavicle is that appendicular or axial skeleton
appendicular
what is bone made of
comprised of collagen fibres that are impregnated by a crystal-line calcium salt.
a bone generally consists of three things, what are they
spongy bone, compact bone and medullary cavity
what are all the classifications of bone shapes
FLISSP
Flat
Long
Irregular
Short
Sesamoid
Pneumatic
whats a pneumatic bone
contains air filled cavities eg skull
what are the two functions of a sesamoid bone?
absorb and redistribute weight-bearing forces
decrease friction
there are three ‘sections’ of a long bone, tell me their location
epiphysis i.e. rounded end,
then metaphysis as the neck,
then diaphysis as the shaft
The metaphysis contains a highly metabolic set of tissues, including what three things
The metaphysis contains a highly metabolic set of tissues, including trabecular bone, blood vessels, and Marrow Adipose Tissue.
think tbm
what portion of bone can be defined as the wide portion of the long bones.
metaphysis
when does the metaphysis develop and what is it a part of
during childhood, its a part of the growth plate
where is the ossification centre of the metaphysis
located close to the end of the bone
what’s the narrow portion of bone that contains the epiphyseal growth plate
metaphyseal
what’s the rounded prominence at the end of the bone, that often forms part of a joint, called
condyle
condyle vs epicondyle
condyle is smooth, whereas epicondyle is rough
epicondyle is attachment site for muscle,
condyle is articulation for another bone
epicondyles actually sit on condyles
explain the structure of compact bone
harversian systems/osteons > harversian canal > houses nerves and blood vessels
cylindrical structures of osteons/harversian systems called concentric lamellae
lacunae are the ant like things where osteocytes (mature bone cells) are located > canaliculi
differences between harversian systems and osteons
no difference, they’re the same thing
what lines the inner spongy bone tissue
endosteum
what lines the outside of the bone
periosteum
where is interstitial lamellae located
between osteons
what are lacunae/ osteocytes responsible for
maintaining the bone matrix
whats the canaliculi, and purpose
small canals that extend in many directions from the lacunae, connecting to others for intercellular communication and passageway for nutrients to osteocytes
so you know we have Haversian canals, what are Volkmann/transverse canals?
they connect these canals transversely, house nerves and blood vessels
structure of spongy bone
lattice like branches called trabeculae, composed of endosteum
does spongy bone contain osteocytes and canaliculi
yes mate
why trabeculae
distribute pressure
What type of bone is found in the marrow cavity? .
spongy bone
where to find spongy bone
it forms epiphyses of long bones, and is found in the bone marrow
growth via increase in width =
appositional
growth via increase in length =, and how
interstitial
growth occurring through cell division in the epiphyseal growth
Which gives rise to appositional bone growth, periosteum or endosteum?
periosteum
how does bone remodelling work
osteoclasts break down old bone
osteoblasts build new bone
how do osteoclasts break down old bone
resorb bone matrix
‘Ruffled border’ releases acid to dissolve bone matrix
Howship’s lacunae – resorption pits that’s created therefore
where are osteoclasts derived from
haematopoietic stem cells
what’s the origin of osteoblasts?
mesenchymal stem cells
where are osteoblasts created
periosteum & endosteum
function of osteoblasts
Function: produce bone matrix (unmineralised matrix = osteoid) & initiate calcification
Become osteocytes once surrounded by matrix
where do osteocytes come from, what is their function?
osteoblasts become osteocytes once surrounded by matrix, no known purpose
which cell senses crack in bones
osteoblast
