Ch. 10 - Anatomy of the Muscular System Flashcards
The body contains more than _____ skeletal muscles
600
skeletal muscle is ____ % to ____% of body weight
40 - 50
Muscles, along with the skeleton, determine the ________ and ___________ of the body
form and contour
Skeletal muscles vary considerably in the following 3 things:
- size
- shape
- fiber arrangement
size of muscle ranges from:
extremely small to large masses
11 muscle shapes
broad, narrow, long, tapering, short, blunt, triangular, quadrilateral, irregular, flat sheets, or bulky masses
6 types of muscle arrangement
- parallel
- convergent
- pennate
- fusiform
- spiral
- circular
the direction of muscular fibers is significant because of its relation to __________
function
2 points of muscular attachment
Origin
Insertion
attachment of muscle that is “point of attachment that does not move when the muscle contracts”
origin
attachment of muscle that is “point of attachment that moves when the muscle contracts”
insertion
Most movements are produced by the ___________ action of several muscles; some muscles in the group _________ while others _________
coordinated
contract
relax
a muscle that directly performs a specific movement
Prime mover
any “mover” muscle that directly performs a movement, including the prime mover
Agonists
muscles that, when contracting, directly oppose prime movers; relax while the prime mover (agonist) is contracting to produce movement; provide precision and control during contraction of prime movers
Antagonist