Ch 6.1 Flashcards
Diaphysis
Center portion of bone. Composed primarily of compact bone with a hollow center
Medullary cavity
The hollow center of the Diaphysis. Some spongy bone lines the medullary cavity.
Epiphyses
Ends of long bone. Mostly spongy bone with an outer layer of compact bone
Sinuses
within some flat and irregular bones of skull, air fill spaced lined by mucous membranes
Centers of ossification
locations in membrane where ossification begin. These centers expand to form bone by gradually ossifying the membrane. Centers have oldest bone and expanding edges have newest bone
Fontanels
Aka soft spots, have more membrane and have not yet been ossified.
Cartilage model
Hyaline cartilage from which bone will be formed
Bone collar
Compact bone, produced by Osteoblasts, on the surface of the cartilage model
Hypertrophy
Aka Enlarge
increase or growth of cells
Calcified cartilage
When hydroxyapatite is made in the cartilage
Primary ossification center
First area of bone to start ossifying
Secondary ossification center
are created in the epiphyses (ends of bones)
Endosteum
A membrane lining the inner surface of the bony wall
Vitamin D
Necessary for normal absorption of calcium from intestines.
Body can ingest or synthesis vit D
Rate of synthesis increases when exposed to sunlight
Rickets
Disease in children with insufficient vit D. Creates bowed bones and inflamed joints
Osteomalacia
Aka adult rickets
A softening of bone tissues due to calcium depletion
Vitamin C
Necessary for Osteoblasts to synthesize collagen
Scurvy
Vit C deficiency marked by ulceration and hemorrhage in any area of body
Growth horomone
Secreted by anterior pituitary, increases general tissue growth, overall bone growth
Thyroid hormones’
Also required for normal growth of all tissues. Decrease in hormones’ can result in smaller individuals
Reproductive hormones
Also regulate bone growth, cause ossification at epiphyseal plates
Bone remodeling
Osteoclast remove old bone and Osteoblast deposit new bone
Converts woven bone into lamellar bone
Basic multicellular unit BMU
temporary assembly of osteoclasts and osteoblasts that travel through or across bone, these cells remove old bone matrix and replace with new bone matrix
Hemotoma
a localized mass of blood released from blood vessels but confined within an organ or space.
Callus
mass of bone tissue that forms at a fracture site
External callus
Encircles the break and connects the broken ends of the bone
Internal callus
forms between the ends of the broken bone, as well in marrow cavity if fracture occurs in diaphysis
Receptor activator of nuclear factor kappa B ligand (RANKL)
cell to cell communication molecule
Receptor activator of nuclear factor kappaB (RANK)
receptor, expressed in the plasma membrane of both undifferentiated and differentiated osteoclasts
Osteoprotegerin
regulatory molecule, prevents osteoclast differentiation by preventing RANKL binding to RANK
Open fracture
End of fractured bone protrudes through open wound
Displaced fracture
Ends of fractured bone move so they are no longer aligned
Spiral fracture
Helical fracture from twisting bone
Comminuted fracture
Results in at least 3 bone fragments, occurs in patients with weakened bodies or severe accidents.
Often requires a surgically placed pin
Greenstick fracture
Fracture with break on one side and bend on other side.
Typical in younger children due to larger amounts of collagen
