The Skeletal System Flashcards
what are the 2 types of membranes
periosteum and endosteum
Periosteum
white, double-layered membrane that covers external surfaces except joints
Fribrous layer
outer layer consiting of dense irregular connective tissue consisting of sharpey’s fibers that secure to bone matrix
Osteogenic layer
inner layer abutting bone and contains primitive osteogenic stem cells that gives rise to most all bone cells
what does the osteogenic layer contain
Contains many nerve fibers blood vessels that continue on to the shaft through nutrient foramen openings
the osteogenic layer is a ________for what structure
anchoring point for tendons and ligaments
Endosteum
Delicate connective tissue membrane covering internal bone surface
list three things about the endosteum
-covers trabeculae of spongy bone -lines canals that pass through compact bone -like periosteum, contains osteogenic cells that can differnciate into other bone cells
list 4 things about Hematopoietic tissue
red marrow- found w/in trabecular cavities of spongy bone -in newborns, medullary cavities, and all spongy bone contain red marrow in adults, red marrow is located in heads of femur and humerus, but most active areas of hematopoiesis are flat bone diploe and some irregular bones(such as the hip bone) -yellow marrow can convert to red if person becomes anemic
list the 5 major cell types of bone tissue
Osteogenic osteoblast osteocytes bone-lining cells osteoclast
osteogenic cells are aka….
osteoprogenitor
what kind of active system cells are in osteogenic cells?
Mitotically active stem cells in periosteum and endosteum -when stimulated, they differentiate into osteoblast or bone-lining cells -some remain as osteogenic cells
osteoblast
bone forming cells that secrete unmineralized bone matrix called osteoid. they’re actively mitotic
osteoid
makes up 90% of bone protein
4 main things about Osteocytes
mature bone- cells in lacunae that no longer divide -maintain bone matrix and act as stress or strain sensors -respond to mechanical stimuli such as increased force on bone weightlessness -communicate information to osteoblasts and osteoclasts (cells that destroy bone) so bone remolding can occur
osteoclasts
derived from same hematopoietic stem cells that become macrophages
osteocytes have what kind of borders
ruffled borders that increase surface area for enzyme degradation of bone
-also helps seal off area from surrounding matrix
central(haversian canal)
runs through the core of osteon
-contains blood vessels and nerve fibers
perforating canals
aka: Volkmann’s canals
- canals lined w/ endosteum that occur @ right angles to central canal
connect blood vessels and nerves of periosteum, medullary cavity, and central canal
lacunae
small cavities that contain osteocytes
canaliculi
hairlike canals that connect bone lacunae to each other and to central canal
osteocytes
secrete bone matrix maintain contact w/ each other and osteocytes via cell projections w. gap junctions
from cervical-sacrum what order does the concave-convex pattern go in
Cervical: Concave
Thoracic: Convex
Lumbar: Concave
Sacrum: Convex
just look at the pic
whats IVDD
Intervertebral disc disease
just look at the pic
severe physical trauma to the spine may result in what condition
herniated(prolapsed) discs
-rupture can result in bones pressing against spinal cord or nerves causing numbness or excruciating pain
Tx for herniated disc?
exercise, massage, heat, painkillers, surgical intervention involving bone grafting to fuse adjoining vertebrae. Percutaneous laser disc decompression vaporises part of disc; tears can be sealed
what causes abnormal spinal curvatures
can be congenital, result from disease, poor posture, unequal pull of muscles on spine
Scoliosis
abnormal lateral rotation of the spine, most often in thoracic region, which may lead to breathing difficulties. May be congenital or result from disease or trauma.
kyphosis
abnormal dorsal curvature common in people with osteoporosis, tuberculosis of the spine, rickets or osteomalacia
lordosis
(swayback) accentuated in lumbar curvature that can result from disease but is also seen in men w/ pot bellies or pregnant women.
aka DQ, OR thots
