Anatomy and Physiology Muscular Vocabulary #2

Creatine Phosphate

A unique high-energy molecule found only in muscle fibers and not in any other cell type.

Aerobic Respiration

Respiration in which oxygen is consumed and glucose is broken down entirely; water, carbon dioxide, and large amounts of ATP are the final products.

Lactic Acid

Product of anaerobic metabolism, especially in muscle

Glycolosis

Breakdown of glucose to pyruvic acid; an anaerobic process.

Muscle Fatigue

Inability of a muscle to contract even though it is still being stimulated.

Oxygen Deficit

The believed cause of muscle fatigue; occurs during prolonged muscle activity.

Isotonic Contractions

“Same tone”; resulting in successful contraction of myofilaments.

Isometric Contractions

Of the same length; contractions in which the muscles to not shorten.

Muscle Tone

Sustained partial contraction of a muscle in response to stretch receptor inputs; keeps the muscle healthy and ready to act.

Flaccid

Soft; flabby; relaxed.

Atrophy

Reduction in size or wasting away resulting from disease or lack of use.

Origin

Attachment of a muscle that remains relatively fixed during muscular contraction.

Insertion

Movable attachment of a muscle.

Flexion

Movement that increases the angle between two parts of the body.

Rotation

Movement of a bone around its longitudinal axis

Abduction

Moving a limb away from the midline of the body.

Adduction

Movement of a limb toward the body midline.

Circumduction

Movement where the proximal end of a limb is stationary, and its distal end moves in a circle; combination of four other movements.

Dorsiflexion

Upward movement of the foot at the ankle.

Plantar Flexion

Depressing the foot, moving the superior surface away from the shin.

Inversion

Turn the sole of the foot medially.

Eversion

Turn the sole of the foot laterally.

Supination

Movement where forearm rotates laterally; radius and ulna are parallel.

Pronation

Movement where the forearm rotates medially; radius and ulna form an “x.”

Opposition

Movement causing the thumb to touch the tips of other fingers.

Prime Mover

Muscle that bears the major responsibility for effecting a particular movement; an agonist.

Antagonist

Muscle that reverses, or opposes the action of another muscle.

Synergist

Muscle that aids the action of a prime mover by effecting the same movement or by stabilizing joints across which the prime mover acts to prevent undesirable movements.

Fixator

Muscle that immobilizes one or more bones, allowing other muscles to act from a stable base.

Extension

Movement in the sagittal plane, decreases angle of the joint.