muscle anatomy Flashcards
what takes up 50% of body mass
muscles
how much heat do muscles in the body produce
at rest
during exercise
20-30%
85%
what is one unexpected function of muscles
glucose control
what does rectus mean
straight
what does vastus mean
open space
what is the very thick facia that separate one muscle compartment from another
inter muscular septa
what are sheets of connective tissue below the skin
facia
what facia layer surrounds entire muscle spindles/fascicles
PERImysium
what facia layer surrounds the entire skeletal muscle
is this thinner or thicker
EPImysium
thinner
what is another word for a muscle cell
fiber
what is a bundle of muscle fibers called
fascicles
what is the facia BETWEEN muscle fibers
ENDOmysium
what provides the chemical environment for a muscle cell (holds everything together)
endomysium
what skeletal muscles are thick in the middle and taper at the ends
are they strong
fusiform
relatively strong
what skeletal muscles are uniform in width and have parallel fascicles to the long axis
are they strong
what’s special about these
parallel
no
they are the majority of muscles in the body
what muscles form rings around the body
circular/sphincter
what muscles approach a tendon from one side
unipenate
what muscles approach a tendon from both sides
bipenate
what muscles form feathers the converge to a single point
multipenate
muscles _____ on bones
pull
what manner of bone pulling has little separation between muscle and bone
direct
what are tendons made of (2)
collagen fibers
elastin proteins
where do collagen fibers run in relation to force within a tendon
parallel
what is a large, sheet like layer of connective tissue that provides structure and distributes tension across a larger number of muscles
aponeurosis
what connective tissue covers tendons from a group of muscles and holds them in place
retinaculum
what type of muscles dont pull on bones, but pull on the skin
face muscles
what muscle provides the major force to complete a movement
the prime moverwh
at muscle opposes the action of the prime mover
the antagonist
why would an antagonist contract
why would an antagonist relax
to prevent excessive movement
to give prime move control
what muscles prevent the movement of bone while the prime mover acts
fixators
what muscle aids the prime mover by adding more force or modifying the direction of a movement
synergist
what is the muscles ability to respond to chemical signals and stretch
excitability
what is a muscles ability to have local electrical excitation
conductivity
what is a muscles ability to return to its original length after being stretched
elasticity
what is the muscles ability to remain stretched after multiple contractions
extensibility
what forms single muscle fibers by being fused together
how does this relate to muscles being multinucleate
myoblast cells
they keep their nuclei
what cells allow for muscle regeneration
they are essentially….
satellite cells
hibernating myoblasts
what results in muscle striations
the arrangements of internal contractile proteins
what helps conduct impulses to the deepest regions of a muscle fiber
T tubules
what is the smooth ER that surrounds a myofibril and acts as a Ca resovoir
sarcoplasmic reticulum
what is the plasma membrane of a muscle fiber
sarcolemma
what is the contractile organelle in a muscle fiber
myofibril
what is the I band made of
actin
what in the M line/ H zone
where myosin is held togetherw
what is the A band
where the filaments overlap
what interlocks thick filaments with the z line
connectin
what protein prevents overstretching and provides muscle recoil
connectin
a sarcomere goes from ____ to ____
z disc - z disc
what are the two heads to a myosin
atp binding
actin binding
what is the protein that calcium binds to that rolls of of the other protein
troponin
what protein is directly on top of the myosin binding site
tropomyosin
what protein links actin in outermost filaments to membrane proteins that link to the endomysium
it acts like _____ that bind cells together
dystrophin
glue
defects in _______ can cause muscular dystrophy
dystrophin
