1. A. Muscle: platysma
B. Origin: connective tissue covering of superior chest muscles
C. Insertion: tissue around mouth
D. Action: tenses skin of neck (shaving)
2. A. Muscle: mentalis
B. Origin: mandible
C. Insertion: skin of chin
D. Action: elevates and protrudes lower lip and pulls skin of chin up (pouting)
3. A. Muscle: orbicularis oris
B. Origin: mandible and maxilla
C. Insertion: skin and muscle around the mouth
D. Action: closes and protrudes lips (kissing); compresses lips against teeth; shapes lips during speech
4. A. Muscle: Corrugator supercilii
B. Origin: medial end of superciliary arch of frontal bone
C. Insertion: skin of eyebrow
D. Action: draws eyebrow inferiorly and wrinkles skin of forehead vertically (frowning)
5. A. Muscle: orbicularis oculi
B. Origin: medial wall of orbit
C. Insertion: circular path around orbit
D. Action: closes eye
6. A. Muscle: occipitofrontalis (frontal belly)
B. Origin: epicranial aponeurosis
C. Insertion: skin superior to supraorbital margin
D. Action: draws scalp anteriorly, raises eyebrows, and wrinkles skin of forehead horizontally (surprise)
Reference:
Marieb, E. and Keller, S., 2018. Essentials of Human Anatomy & Physiology. 12th ed. Pearson Education Limited, pp.242.
Tortora, G. and Derrickson, B., 2011. Principles of Anatomy and Physiology. 13th ed. Wiley Custom, pp.376-377.