Ch. 7.5 Muscular System Key terms
what is Abduction
Moving a body part away from the midline.
what is Adduction
Moving a body part toward the midline.
what is Cardiac muscle
Forms the walls of the heart and contracts to circulate blood.
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 Contractibility
Muscle fibers that are stimulated by nerves contract, or become short and thick, which causes movement.
what is Contracture
A severe tightening of a flexor muscle resulting in bending of a joint.
what is Dorsiflexion
Bending backward or bending the foot toward the knee.
what is Elasticity
Allows the muscle to return to its original shape after it has contracted or stretched.
what is Excitability
Excitability: Irritability, the ability to respond to a stimulus such as a nerve impulse.
what is Extensibility
The ability to be stretched.
what is Extension
Increasing the angle between two bones, or straightening a body part.
what is Fascia
A tough, sheetlike membrane that covers and protects the tissue.
what is Flexion
Decreasing the angle between two bones, or bending a body part.
what is Insertion
The end of the muscle that moves when the muscle contracts.
what is Involuntary
Function without conscious thought or control (applies to cardiac and visceral muscle).
what is muscle tone
The state where muscles are partially contracted at all times, even when not in use
what is Muscular system
The system made up of more than 600 muscles.
whay is Origin
The end of the muscle that does not move when the muscle attaches to a bone.
what is Plantar flexion
Bending forward or bending the foot away from the knee.
what is Pronation
Turning a body part downward.
what is Rotation
turning a body part around its own axis; for example, turning the head from side to side.
what is Skeletal muscle
Muscle that is attached to bones and causes body movement.
what is Supination
: Turning a body part upward.
what are Tendons
Strong, tough, fibrous connective-tissue cords that attach muscles to bones.
what is Visceral muscle
Also called smooth muscle, it is found in the internal organs of the body, such as those of the digestive and respiratory systems, and the blood vessels and eyes. It contracts to cause movement in these organs.