5b - Skeletal Components Flashcards
What three things comprise the cartilage matrix?
proteoglycans
collagen
elastin
What is different in the matrix of hyaline and elastic cartilage?
proportions of the components of the matrix
the diaphysis is the bone ___.
bone shaft
What is the epiphysis on a bone?
the regions at the two ends of the shaft (diaphysis) “caps”
diaphysis contains ___ bone
compact
epiphysis contains ___ bone
spongy bone
blood cell generations happen in ___ marrow
red marrow
yellow marrow contains ___
adipocytes
the dense irregular CT layer on the outer bone surface is called ____
periosteum
mechanical stress and fractures stimulate bone ___
remodeling
remodeling = ____ + _____
remodeling = resorption and ossification
resorption is by ___
osteoclasts
the deposition is by ___
osteoblasts
the bone matrix mineral components is mostly ___
hydroxyapatite
what is hydroxyapatite made of
calcium/phosphate polymer
what happens to a bone when the organic matrix is removed?
will shatter easily; becomes brittle.
What happens when the inorganic matrix is removed from the bone?
bones bend easily without their inorganic matrix (minerals). Cannot resist compression.
what are the features of spongy bones?
has spicules and blood vessels move through spaces
what are the features of compact bone?
dense bone with canal systems for blood vessels. Run parallel to the shaft.
what are osteoblasts and what do they do?
- immature cells. Some can become osteocytes (most don’t).
- They lay down a new matrix
- signal to and control osteoclasts formation and activity
what are osteocytes and what do they do
- mature cells found in lacunas
- detects bone deformation
- signals to osteoblasts to begin bone replacement or repair
What is unique about mesenchymal stem cells?
can become chrondrocytes or osteoblasts.
osteocytes send cell extensions through ___
canaliculi
canaliculi provide channels in a matrix for ___ exchange and allow osteocytes to connect in a large web via ___ ___
fluid exchange via gap junctions
