Ch. 7.5 Muscular System Key terms
Abduction
Moving a body part away from the midline.
Contracture
A severe tightening of a flexor muscle resulting in bending of a joint.
Extension
Increasing the angle between two bones, or straightening a body part.
Muscle Tone
This state of partial contraction is called muscle tone and is sometimes described as a state of readiness to act.
Visceral Muscle
Is found in the internal organs of the body, such as those of the digestive and respiratory systems, and the blood vessels and eyes.
Adduction
Moving a body part toward the midline.
Dorsiflexion
Bending backward or bending the foot toward the knee.
Fascia
A tough, sheetlike membrane that covers and protects the tissue.
Muscular System
The system known as the muscular system.
Skeletal Muscle
It is attached to bones and causes body movement.
Cardiac Muscle:
Forms the walls of the heart and contracts to circulate blood.
Elasticity
Allows the muscle to return to its original shape after it has contracted or stretched.
Flexion
Decreasing the angle between two bones, or bending a body part.
Origin
The end that does not move (when a muscle attaches to a bone).
Supination
Turning a body part upward.
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.
Excitability
Irritability, the ability to respond to a stimulus, such as a nerve impulse.
Insertion
The end that moves when the muscle contracts.
Plantar Flexion
Bending forward or bending the foot away from the knee.
Tendons
Strong, tough, fibrous connective-tissue cords.
Contractibility
Muscle fibers that are stimulated by nerves contract, or become short and thick, which causes movement.
Extensibility
The ability to be stretched.
Involuntary
Function without conscious thought or control.
Pronation
Turning a body part downward.
Voluntary
Because a person has control over its action.