skeletal system Flashcards
what type things does the skeletal system balance
acid/ base
electrolyte
what two things does the skeletal system produce
blood
hormones
what is another word for compact bone
cancellous
what lines the outside of bones
periosteum
what…
lines the internal marrow cavity
covers all the honeycombed surfaces of spongy bone
lines a canal system found throughout the compact bone.
endosteum
where is red bone marrow found
epiphysis
where is yellow bone marrow found
diaphysis
what is the epiphysis
ends of bone
what is the diaphysis
shaft of bone
what is articular cartilage
caps on the ends of epiphysis
what produce osteoblasts and osteocytes
osteogenic cells
what build bone
osteoblasts
what are trapped within the matrix and maintain bone tissue
osteocytes
what are the projections on osteocytes
what do they do
canoluli
communicate with other osteocytes
what were osteocytes originally before they became trapped in the matrix
osteoblasts
what “chew up” bone
osteoclasts
what enzyme do osteoclasts release
acid proteases
what bone cell releases calcium when doing its job
osteoclasts
what type of bone cell are multinucleate
osteoclasts
what do osteocytes imbed themselves in (their capsule)
lacuna
from superficial to deep, what are the 3 layers of the skeletal system (starting with osteoblasts)
osteoblasts
osteoid
mineralized bone
what protein is mixed in with the skeletal system during early mineralization
collagen
what unit make up compact bone
what shape are they
osteons
circular
what is the bone between the circular osteons
interstitial lamellae
what is another word for the osteon system
Haversian system
what is the unit the makes up spongey bone
trabeculae
how does spongy bone get its nutrients (since its avascular)
red bone marrow
is compact bone vascular
yes
what type of bone is usually found along areas of physical stress
spongey bone
what is practically the only type of bone marrow in children
red
-
-
what is pre bone tissue called
osteoid tissue
where is the primary ossification center of long bone formation in an early cartilage model
in the center of the cartilage model
at birth, where is the secondary ossification center
at the ends of the bones, closer to epiphysis
what does the epiphysial plate become when long bones are done growing
the epiphysial line
in bone lengthening, what are the 5 zones of bone from cartilage to spongey bone
reserve cartilage
cell proliferation
hypertrophy
calcification
bone deposition
where is the cessation of mitosis in bone lengthening
zone of cell hypertrophy
where do osteoblasts originate
under the periosteum
how is bone widened
a blood vessel creates a ridge, and the vessel eventually gets engulfed
what is the canal called that aids vessels connecting in bone widening
perforating canal
after an initial osteon is formed during bone widening, what packs around that to widen the bone even further
circumferential lamella
what percent of the skeleton is remodeled throughout the year
10%
what are 3 uses of bone remodeling
hint: repair ___, release _____, _____ bone in response to use and disuse
repair micro fractures
release minerals into blood
reshape bone in response to use or disuse
what is Wolffs law of bone
bone shape is determined by mechanical stress put upon it
what two bone cells are active during bone remodeling
osteoblasts and osteoclasts
what tend to grow bigger on bones in response to mechanical stress
boney processes
what hormone tones bones by depositing calcium onto them
calcitonin
what gland releases calcitonin
thyroid
when there is increased calcium in blood, what happens in the kidneys
reabsorption decreases
when calcium absorption decreases in the kidneys, what happens to blood calcium levels
it decreases
what hormone is released when blood calcium is low
parathyroid hormone
how does calcium absorption in the small intestine increase
vitimin D synthesis
when calcium levels are low, how do the kidneys play a role
calcium is reabsorbed from urine
what is the process in which calcium, phosphate, and other ions are taken from blood and deposited in bone
mineralization
what is the process of dissolving bone and releasing minerals into blood
mineral reabsorption
where do osteoclasts perform mineral reabsorption
ruffled boarder
what hormone is responsible for absorption of calcium by the digestive tract to put into bone
calcitriol
what 2 hormones are responsible for the reabsorption of calcium by the kidneys to be put into blood
calcitriol and PTH
what hormone is responsible for the deposition of calcium onto bones by osteoblasts
calcitonin
what two hormones are responsible for the reabsorption of calcium from bone via osteoclasts to be put back into blood
calitriol
PTH
what is the most active form of vitimin D
calcitriol
what gland releases calcitonin
thyroid gland
what cells of the thyroid gland release calcitonin
C cells (clear cells)
what hormone may inhibit bone loss in pregnant and lactating women
calcitonin
what hormone has a weak effect in adults, but a strong effect in children
calcitonin
PTH is released when calcium levels are ____
low
what are the 4 ways PTH increases calcium in blood
releases _______ from bone
reduces _____ absorption by ______
activated ______ absorption in gut
inhibits the production of _____ ______
calcium
calcium, kidneys
vitimin D
collagen fibers
what hormone raises phosphate levels
calcitriol
phosphate in blood is regulated as much as calcium levels
true or false
false, theyre regulated much less
how does calcitriol raise blood phosphate levels
promotes absorbtion of P by small intestine
what hormone lowers blood phosphate levels
PTH
how does PTH lower blood P levels
promotes its urinary excretion
what type of hormones cause bone growth to stop
anabolic steroids
how can HGH stunt growth
you run out of epiphysial plate and it becomes an epiphysial line prematurely
2 different hormones affect bone tissue, what are they
(besides the ones involved in Ca and P regulation)
estrogen and testosterone
what hormone is great at bone growth, but is shorter term
estrogen
this explains why girls in elementary school are bigger than boys, but the reverse is true for high school aged children.
what is a perpendicular/ butt joint fracture
transverse
what is an angled fracture
oblique
what is a twisted fracture
spiral
what is a fracture that results in more than two peices of bone being broken off
comminuted
what is when one epiphysis breaks ooff
avulsion
what is a fissure caused by downward pressure called
impacted
what is a crack in the middle of a bone called
fissure
what is a fracture in a child called when the bone bends slightly
greenstick
what are the 4 phases of bone fracture repair
hematoma formation
soft callous formation
hard callous formation
bone remodeling
what 6 things make up the axial skeleton
skull
vertebrae
sternum
ribs
sacrum
hyoid
what type of skeleton does the pectoral girdle and pelvic girdle have
appendicular
about how many bones does an adult have
about how many bones does one have at birth
206
270
what bones make the number of bones in someone vary
sesamoid bones
