Activity 1
Name the muscle that may cause the following facial expression and write down its origin, insertion and action.
- MUSCLE - Platysma
ORIGIN - Fascia over parotid (Salivary) gland
INSERTION - Skin at angle of mouth.
ACTION - Draws angle of mouth laterally, as in grimacing.
2. MUSCLE - Mentalis
ORIGIN - Mandible
INSERTION - Skin of chin.
ACTION - Elevates and protrudes lower lip and pulls skin of chin up, as in pouting.
3. MUSCLE - Orbicularis Oris
ORIGIN - Muscle fibers surrounding opening mouth.
INSERTION - Skin at corner of mouth.
ACTION - Closes and protrudes lips, as in kissing; compresses lips against teeth; and shapes lips during speech.
4. MUSCLE - Corrugator Supercilii
ORIGIN - Medial end of superciliary arch of frontal bone.
INSERTION - Skin of eyebrow.
ACTION - Draws eyebrow inferiorly and wrinkles skin of forehead vertically as in frowning.
5. MUSCLE - Orbicularis Oculi
ORIGIN - Media wall of orbit.
INSERTION - Circular path around orbit.
ACTION - Closes eye.
6. MUSCLE - Frontal Belly
ORIGIN - Epicranial Aponeurosis.
INSERTION - Skin superior to suborbital margin.
ACTION -Draws scalp anteriorly, raises eyebrows, and wrinkles skin of forehead horizontally as in look of surprise.