Bone Flashcards
names for spongy bone
cancellous, trabecular, spongy
names for compact bone
cortical, lamellar, compact
where is spongy bone found
within epiphyses (but is covered with a layer of compact bone) of long bones, between the thick plates of the skull’s flat bones (diploe)
where is compact bone found?
the diaphysis of long bones (but has a thin layer of spongy lining the bone marrow cavity), thin covering surrounding epiphyses, tables/plates of flat bones - always lamellar bone
composition of outer layer of periosteum
fibrous layer of dense irregular connective tissue with collagen fibers, fibroblasts, blood vessels, nerves
composition layer of inner layer of periosteum (cellular layer)
periosteal (osteoprogenitor cells)
what are sharpey’s fibers
collagen fibers that extend into bone and are continuous with collagen fibers of the extracellular matrix - they are the sticky fibers that help connect periosteum to bone
what is the endosteum
thin layer of simple epithelium that lines internal marrow cavities and contains osteoblasts and osteoprogenitor cells
what is the periosteum
fibrous, vascular, nerve-containing outer layer of collagen bundles and fibroblasts and inner layer of osteoprogenitor cells
circular components of compact boneq
osteon, with central or Haversian canal in center
what is within Haversian canals?
vasculature, lymph, nerves (neurovascular bundle)
osteon made of
concentric lamellae with lacuna that houses the osteocytes
what is canaliculi
dendritic processes coming off of the lacuna (where the osteocyte is) that contain gap junctions that allow osteocytes to communicate
what role does the osteocyte play?
controls metabolic and remodeling rate of bone
what is a haversian canal
central canal in osteon containing neurovasculature, and runs parallel to bone length
waht is a volkman’s canal or perforating canal
vascular canal running perpendicular to bone length
what is lacuna
an embedded, hollowed out area between lamella that house osteocytes, are filled with canaliculi for cell communication
what is lamaella
concentric rings of compact bone that make up osteon rings
how do lamellae maintain strength while keeping a light weight?
regular bone remodeling/maintenance provides differing fiber orientations
what are the bony parts between spaces in spongy bone?
trabeculae/spicules
where is red bone marrow located and what is the function
epiphyses, site of hematopoiesis (synthesizes RBC, WBC, platelets)
where is yellow bone marrow located
diaphysis
osteoblasts
synthesis of bone matrix, rounded cells forming a simple row along outer edge of bone
osteoclasts
bone degeneration/resorption, large and motile and multinucleated cells derived from monocytes
MACROPHAGES THAT SECRETE ACID AND PROTEASES and COLLAGENASE TO BREAK DOWN BONE MATRIX