Chapter 10 The Muscular System
What are the 4 functional group classifications of muscle?
How are skeletal muscles named?
by location, shape, size, direction of muscle fibers, number of origins, location of attachments, muscle action
What are the 4 main arrangements of fascicles?
circular, convergent, parallel, pennate
What is a lever?
rigid bar that moves on a fixated point (bone)
What is a fulcrum?
the fixed point (joint)
What is the effort?
the source that is applied to a lever (muscle)
What is the load?
the resistance that is moved (bone, tissue, objects being moved)
What do lever do?
they also given effort to move a heavier load; move a load further or faster
What is mechanical advantage?
load is close to the fulcrum
large load over small distance
What is mechanical disadvantage?
load far from fulcrum
load moves rapidly over long distance and wide rang of motion
What are the muscle used in mastication?
Temporalis, masseter - jaw closure
medial and lateral pterygoids - grinding movement
buccinator - chewing
What are the muscles of the erector spine (sacrospinalis)?