Ch. 7.5 Muscular System key Terms
abduction
moving a body part away from the midline
adduction
moving a body part toward the midline
cardiac muscle
forms the walls of the heart and contracts to circulate blood
circumduction
moving in a circle at a joint or moving one end of a body part in a circle while the other end remains stationary
contractibility
muscle fibers that are stimulated by nerves contract or become short and thick which causes movement
contracture
a severe tightening of a flexor muscle resulting in bending of a joint
dorsiflexion
bending backward or bending the foot toward the knee
elasticity
allows the muscle to return to its original shape after it has contracted or stretched
excitability
irritability, the ability to respond to a stimulus such as a nerve impulse
extensibility
ability of muscle tissue to be stretched or lengthened beyond its resting length without being damaged
extension
increasing the angle between two bones or straightening a body part
fascia
a tough, sheetlike membrane that covers and protects the tissue
flexion
decreasing the angle between two bones or bending a body part
insertion
end that moves when the muscle contracts
involuntary
muscles that contract without conscious thought or control
muscle tone
state of partial contraction
muscular system
a system made up of 600 muscles
origin
the end that doesn’t move when a muscle is attached to a bone
plantar flexion
bending forward or bending the foot away from the knee
pronation
turning a body part donward
rotation
turning a body part around its own axis
skeletal muscle
attached to bones and causes body movement
supination
turning a body part upward
tendons
a cord that attaches a bone to muscle
visceral muscle
found in the internal organs of the body; causes movement in organs