11.1 -11.5 Flashcards
fascicles
bundles of muscle fibers
muscles are classified based on
the pattern of fascicle arrangement
types of skeletal muscles (4)
parallel muscles
convergent muscles
pennate musccles
circular muscles
parallel muscles
fascicles are parallel to long axis of muscle
- can be flat or spindle w/ a central BODY
convergent muscles
muscle fascicles spread in a broad area on 1 side and converge on an attachment site on the other
pennate muscles
the fascicles form a common angle with the tendon, take on a feather like appearance
types of pennate muscles
unipennate - all fasicles on same side of tendon
bipennate - fascicles on both sides of a central tendon
multipennate - tendon branches within the muscle
circular muscles (sphincters)
fascicles are concentrically arranged around an opening
lever
rigid structure that moves on a fixed point called a fulcrum
a lever moves when
muscles provide a pressure called applied force (AF) to overcome a load (L)
lever function
change the direction of applied force
change the effective strength of applied force
3 classes of levers
1st, 2nd, and 3rd class
1st class lever
fulcrum lies between the applied force and the load
- like a crowbar / extension of the neck + lifting the head
2nd class lever
the load lies between the applied force and the fulcrum
- like a wheelbarrow..small force can be used to move large weight
– ankle extension by calf muscles
3rd class lever
applied force is between the load and the fulcrum
- like a pair of tongs
origin
fixed point of attachment of a muscle to a bone
insertion
more movable point of attachment of a muscle to a bone
action
specific movement produced by the contraction of a muscle
- ex: adduction, elevation
agonist (prime mover)
main muscle responsible for producing a particualr movement
4 functional types of muscles
-agonist/prime mover
-antagonist
-synergist
-fixator
antagonist
opposed the movement of the agonist
synergist
a smaller muscle that assists an agonist
fixator
a synergist that assists an agonist by preventing movement at another joint
externus (superficialis)
muscles visible at body surface
internus (profundus)
deeper muscles
extrinsic
superficial muscle that positions or stabilizes an organ
– outside the structure
intrinsic
located entirely within an organ
transversus
runs across the longitudinal axis of the body
oblique
runs at a slant to the longitudinal axis of the body
rectus
straight muscle that runs along the longitudinal axis of the body
for origin and insertion, the first part of the name
1st part of the name indicates origin
2nd part indicates insertion
terms indicating shape (11)
deltoid
orbicularis
pectinate
piriformis
platysma
pyramidal
rhomboid
serratus
splenius
teres
trapezius
deltoid
triangle
orbicularis
circle
pectinate
comb like
piriformis
pear shaped
platysma
flat plate
pyramidal
pyramid
rhomboid
parallelogram
serratus
serrated/zig zag
splenius
bandage
teres
round and long
trapezius
trapezoid
alba
white
brevis
short
gracilis
slender
latae
wide
latissimus
widest
longissimus
longest
longus
long
magnus
large
major
larger
maximus
largest
minimus
smallest
minor
smaller
abductor
movement away
adductor
movement toward
depressor
lowering movement
extensor
straightening movement
flexor
bending movement
levator
raising movement
pronator
turning into prone position
supinator
turning into supine position
tensor
tensing movement
buccinator
trumpeter
