Chapter 10 Vocabulary Anatomy & Physiology Honors

7.Extension

Extension is a muscle action produced when the muscle crosses on the posterior side of a joint. *The latissimus dorsi is the antagonist of the pectoralis major, extension takes place here.

24.Opposition

Opposition is the movement that moves the thumb toward the little finger. *Opposition helps us grip things.

19.Eversion

Eversion is the muscle movement that turns the sole of the foot outward so that its lateral border is elevated. *The fibularis brevis the prime mover of foot eversion.

4.Fixators

A fixator is a stable base that is used by synergist muscles to immobilize a bone or a muscle's origin. *The fixator muscles that run from the axial skeleton to the scapula can immobilize the scapula so that only the desired movements occur at the mobile shoulder joint. *Fixators can also be known as muscles that maintain upright posture.

1.Prime mover or agonist

A primer mover or agonist is a muscle that has the major responsibility for producing a specific movement. *One example of a prime mover is the pectoralis major muscle, which flexes out the anterior chest and makes the arm flexion movement.

9.Abduction

Abduction is the muscle action produced when a muscle crosses on the lateral side of a joint. *An example of abduction would happen in the deltoid middle fibers.

10. Adduction

Adduction is a muscle action produced when the muscle crosses on the medial side of a joint. *The teres major is the antagonist of the deltoid which causes adduction.

5.Angular Movements

Angular movements is the group of muscle movements that increase or decrease the angle between two bones. *Angular movements may occur in any plane of the body.

2.Antagonist

Antagonist is a type of functional muscle that opposes or reverses a specific movement. *Antagonist muscles help regulate the action of a prime mover by contracting slightly to provide some resistance.

11.Circumduction

Circumduction is the muscle action consists of the movements of flexion, abduction, extension and adduction (performed in sequence). *Circumduction is a circular movement permitted at ball and socket, condylar and saddle joints.

23.Depression

Depression is the movement of the elevated part inferiorly. *The scapula is depressed largely by gravity (the weight of the arm).

16.Dorsiflexion

Dorsiflexion is a movement that prevents toes from dragging during walking. *Dorsiflexion is not considered to be a powerful movement under the categories of movements of ankles and toes.

22.Elevation

Elevation is the muscle movement that lifts a body part superiorly. *The scapulae are elevated when you shrug your shoulders.

6.Flexion

Flexion is a muscle action where a muscle crosses the anterior side of a joint. *The pectoralis major is an example of a muscle that crosses the side of a joint when the arm is swinging to the front.

8.Hyperextension

Hyperextension is a muscle action that is considered extreme or even abnormal extension. *Contracting the abdominal muscles as the deep back muscles contract helps prevent hyperextension of the spine and splints the entire body trunk.

18.Inversion

Inversion is the muscle movement that turns the sole of the foot inward so that the medial border of the foot is elevated. *Tibialis posterior is the prime mover of foot inversion.

17.Plantar flexion

Plantar flexion is the muscle movement of the ankle (and foot) where it provides the forward thrust when walking or running. *Plantar flexion is considered to be a powerful movement because it lifts the weight of the entire body.

15.Pronation

Pronation is the movement done by pronator teres and pronator quadratus which consists of turning the palm posteriorly or downwardly. *Pronation originates in medial epicondyle of humerus; coronoid process of ulna.

20. Protraction

Protraction is a nonangular anterior-posterior movements in a transverse plane. *The mandible is protracted when you jut out your jaw.

21.Retraction

Retraction is a nonagular anterior-posterior movement in a transverse plane. *The mandible is retracted when you bring back or contract the jaw.

12. Rotation

Rotation is the movement where a joint turns the moving bone about its axis. *Rotation toward the body is internal or medial rotation; rotation away from the body is external or lateral rotation.

13. Special Movements

Special movements are the kind that do not fit under any other category of movements. *Special movements include supination, pronation, inversion, eversion, protraction, retraction, elevation, depression, opposition, dorsiflexion, and plantar flexion.

14.Supination

Supination is the movement done by the supinator muscle, which is turning the palm anteriorly or upward. *The origin for the supination is in the lateral epicondyle of humerus; proximal ulna.

3.Synergists

Synergists are the type of functional muscles that primer movers add a little extra force to the same movement or can also reduce unnecessary movements as the prime mover contracts. *synergistic muscles would help stabilize the wrist when a person is making a fist (that's why the wrist doesn't bend when it's in a fist).