chapter 11- muscular system Flashcards
the fascicle arrangement of what muscle allows for the muscle to move the load over a great distance?
parallel
explain the fascicle arrangement of a convergent muscle?
spread out on one end, all bunched together at the other
which fascicle arrangement is best for producing the most tension?
pennate
a concentric arrangement of fascicles describes what muscle?
circular (sphincter)
what is the place on the skeletal system where the moveable end of a muscle attaches?
insertion
is the term “move” an appropriate action term for a muscle, explain?
no, action is a specific movement (ex: flex, extend, abduct, etc.), and the part being acted upon (ex: flex elbow)
the prime mover in muscle group is called what?
agonist
if two muscles had the same name regarding location and action but one was called profundus and other superficialis, what would you know about their location relative to each other?
superficialis would be stacked over the top of profundus
when the name of a muscle is derived from its origin and insertion, which part comes first in the name?
origin
what is the function of an antagonist in a muscle group responsible for a particular action?
fine-tune the movement
muscle organization
-groups of fiber organized into fascicles
-fibers in fascicle run parallel to fascicle but fascicle can be arranged in 4 different shapes with respect to tendon
parallel muscles (muscle organization)
-fascicles run parallel to length of muscle
-most skeletal muscle arranged this way
-able to change length extensively
-can move load over a great distance
convergent muscles (muscle organization)
-fascicles spread out like fan on one end and converge to single point on other
-produces less tension & distance than parallel muscle
-independent contraction of fascicles can produce different movements from same muscle
-provides versatility
pennate muscles (“feather like”) (muscle organization)
-fascicles are arranged at an angle to tendon
-pennate muscle produce more tension than parallel muscles but can’t move as far
unipennate
fascicles angled on one side of tendon
bipennate
tendon in middle with angled fascicles on either side
multipennate
branched tendon with fascicles organized around each branch
circular muscles (sphincters)
-concentric arrangement of fascicles
-function to decrease diameter of openings, guard entrances & exits
orgin
where the fixed end of muscle attaches to bone, cartilage, or CT
insertion
where the moveable end attaches
action
specific movement produced by the muscle during contraction
why do muscles work in groups?
-increase tension or fine-tune movement
-different muscles serve different function
agonist
prime mover, muscle most responsible for the specific action
synergist
a muscle with the same action as the agonist, assists agonist at the beginning of contraction when fiber length isn’t optimal for agonist
