Ch. 7.5 Muscular System Key terms
moving a body part away from the midline.
What is contracture
a severe tightening of a flexor muscle resulting in bending of a joint.
What is extension
increasing the angle between two bones, or straightening a body part.
What is muscle tone
a state of partial contraction that is always present, even when not in use.
What is rotation
Turning a body part around its own axis, for example, turning the head from side to side.
What is adduction
moving a body part toward the midline.
What is dorsiflexion
: bending backward or bending the foot toward the knee.
What is fascia
a tough, sheetlike membrane that covers and protects the tissue.
What is Muscular System
the system made up of more than 600 muscles in the body.
What is Skeletal muscle
muscle that is attached to bones and causes body movement.
What is cardiac muscle
forms the walls of the heart and contracts to circulate blood.
What is elasticity
the ability to allow the muscle to return to its original shape after it has contracted or stretched.
What is flexion
decreasing the angle between two bones, or bending a body part.
What is origin
the end that does not move when the muscle contracts.
What is supination
turning a body part upward.
What is 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, such as swinging an arm in a circle.
What is excitability
irritability, the ability to respond to a stimulus such as a nerve impulse.
What is insertion
the end that does move when the muscle contracts.
What is plantar flexion
bending forward or bending the foot away from the knee.
What is tendons
strong, tough, fibrous connective-tissue cords which are used by muscles to attach to bones.
muscle fibers that are stimulated by nerves contract, or become short and thick, which causes movement.
What is extensibility
the ability to be stretched.
What is involuntary
meaning the muscle fibers function without conscious thought or control (applies to cardiac and visceral/smooth muscle).
What is pronation
turning a body part downward.
What is visceral muscle
muscle found in the internal organs of the body, such as those of the digestive and respiratory systems, and the blood vessels.