Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
17 Cards in this Set
- Front
- Back
|
what type of collagen is used in bone?
|
type 1
|
|
|
how is immature bone different from mature?
|
- not laminated, collagen is irregular and random
- cytes are larger, rounder, and more abundant - only in young or with injury |
|
|
what to osteoblasts make?
|
- osteoid, mainly collagen
- alkaline phosphatase (involved in mineralization) |
|
|
what receptors do osteobasts have?
|
- for 1,25-D and parathyroid hormone
- probably involved in Ca ion exchange |
|
|
where are osteocasts found?
|
in howship lacunae
|
|
|
what do osteocasts secrete?
|
acid phosphatase and other proteases
|
|
|
preosteobast
|
- w/ blasts on surface
- dont form bone yet - are capable of dividing, unlike basts |
|
|
bone surface cells
|
- inactive bast
- cover bone surface not being remodeled - separate bone surface from ECF, making a separate bone-fluid compartment |
|
|
periosteum in kids vs adults
|
- kids - thick w/ blasts and prebasts - active
- adults - thin w/ dormant basts - may be activated by trauma |
|
|
how is cancellous bone formed and what is its function?
|
- formed by basts lining the trabeculae
- large surface area, so it responds quickly to physical and metabolic demands (remodeling rate is higher) |
|
|
1o vs. 2o haversian systems
|
- 1o formed on growing surface, blasts close in the vessels
- 2o formed form casts that make respoption canals w/ cutting cone - vessels follow, then basts close it up |
|
|
how are cubiodal bones enlarged
|
- deep cartilage cells of AC divide and are replaced by bone, and AC cartilage is pushed out
- same w/ ephiphysis |
|
|
when do epiphysis ossify?
|
- distal femur at birth
- prox femur at 2-3 months - distal radius at 3 years |
|
|
what is 1o spongiosa?
|
- pink bone parallel to the long bone surrounding blue cartilage
- it only extends into the met a few mm - little found in adult |
|
|
rachitic rosary
|
what the ribs are in ricketts, from accumulation of hypertrophic cartilage cells
|
|
|
funnelization
|
when the periphery of bone in the met is is undercut by casts
|
|
|
tubulation
|
when the diaphysis is enlarged trasversely by periosteal growth
|
