BSC2085L_Quiz2_StudyGuide_Newest.pdf

BSC2085L Anatomy-Physiology 1 Lab Quiz 2 Study Guide Flexion is a movement that decreases a joint angle, usually in the sagittal plane. Extension is a movement that straightens a joint and generally returns a body part to the zero position. Abduction is the movement of a body part in the frontal p...

BSC2085L Anatomy-Physiology 1 Lab Quiz 2 Study Guide Flexion is a movement that decreases a joint angle, usually in the sagittal plane. Extension is a movement that straightens a joint and generally returns a body part to the zero position. Abduction is the movement of a body part in the frontal plane away from the midline of the body. Adduction is the movement of a body part in the frontal plane back toward the midline of the body. Elevation is a movement that raises a body part vertically in the frontal plane. Depression is a movement that lowers a body part vertically in the frontal plane. Protraction is the anterior movement of a body part in the transverse (horizontal) plane. Retraction is the posterior movement of a body part in the transverse (horizontal) plane. Rotation is a movement in which a bone spins on its longitudinal axis. Supination is a movement of the forearm that turns the palm to face anteriorly. Pronation is a movement of the forearm that turns the palm to face posteriorly. Opposition means moving the thumb to touch the tip of any of the other four fingers. Dorsiflexion is a movement of the foot in which the toes are elevated. Plantar Flexion is a movement of the foot so the toes point downward. Inversion is a foot movement that tips the medially, somewhat facing each other. Eversion is a foot movement that tips the soles laterally, away from each other. The connective tissue components of a skeletal muscle, from the smallest to largest and from deep to superficial, are as follows: Endomysium. This is a thin sleeve of loose connective tissue that surrounds each muscle fiber. Perimysium. This a thicker connective tissue layer that wraps muscle fibers together in bundles called fascicles. Epimysium. This is a connective layer that surrounds the entire muscle. The effect produced by a muscle is called its action. Muscles can be classified into four categories according to their actions. 1. The prime mover (agonist) is the muscle that produces most of the force during a particular joint action. In flexing the elbow, for example, the prime mover is the brachialis. 2. A synergist is a muscle that aids the prime mover. Two or more synergists acting on a joint can produce more power than a single larger muscle. 3. An antagonist is a muscle that opposes the prime mover. In flexing the elbow, for example, the brachialis is the prime mover and the triceps brachii is the antagonist. When the elbow is extended, their roles are reversed so that the triceps brachii is the prime mover and the brachialis is the antagonist. 4. A fixator is a muscle that prevents a bone from moving. PLEASE NOTE: You will also need to study the muscle tables in your laboratory manual. For each muscle, you will need to know the muscle’s origin, insertion, action, and innervation.