Chp. 13: Gross Anatomy of Muscular Skeleton (Head, Neck, Thorax) Flashcards
Agonists (prime movers)
Muscles responsible for producing a particular movement
Antagonists
Muscles that oppose or reverse a movement
Synergists
Aid the action of agonists by assisting with the same movement or by reducing undesirable or unnecessary movement.
Fixators
Specialization synergists; they immobilize the origin of a prime mover so that all the tension is exerted at the insertion
Rectus
Straight; a muscle with fibers running parallel to the midline
Transverse/ Oblique
Muscles that run at right angles respectively to the midline
Maximus
Largest
Minimus
Smallest
Longus
Long
Brevis
Short
Origin
Stationary, immovable, or less moveable attachment
Insertion
More moveable attachment
Frontal Belly (of Epicranius)
ORIGIN: Epicranial aponeurosis
INSERTION: Skin of eyebrows, root of nose
ACTION: Raises eyebrows
Occipital Belly (of Epicranius)
ORIGIN: Occipital and temporal bones
INSERTION: Epicranial aponeurosis
ACTION: Fixes aponeurosis and pulls scalp posteriorly
Orbicularis Orculi
ORIGIN: Frontal and maxillary bones and ligaments around orbit
INSERTION: Tissue of eyelid
ACTION: Closes Eye