Muscular System P1 Flashcards
SCM origin
Medial part of the clavicle and sternum’s superior and lateral surface
SCM insertion
Mastoid process of the temporal bone
Trapezius origin
External surface of the occipital bone and posterior midline of the cervical and thoracic regions
Trapezius insertion
Lateral third of the clavicle and parts of the scapula
Epicranius origin
Superior nuchal line of the occipital bone and the mastoid process of the temporal bone
Epicranius insertion
The skin of the eyebrow and root of the nose
Orbicularis oculi origin
Orbital rim
Nasal process of the frontal bone
Frontal process of the maxilla
Orbicularis oculi insertion
The skin at the lateral canthus
Corrugator supercilii origin
The supraorbital region of the frontal bone
Corrugator supercilii insertion
The skin of the eyebrow
Orbicularis oris origin
Facial modiolus at the labial commissure
Orbicularis oris insertion
The tissues of the upper and lower lips
Buccinator origin
Alveolar process of the maxilla
Alveolar process of the mandible
Pterygomandibular raphe/fold
Buccinator insertion
The tissues of the orbicularis oris at the corners of the mouth
Risorius origin
The fascia superficial to the masseter
Risorius insertion
The skin at the ipsilateral labial commissure at the facial modiolus
Levator labii superioris origin
The infraorbital rim of the maxilla
Levator labii superioris insertion
The skin at the ipsilateral labial commissure at the facial modiolus
Levator labii superioris alaeque nasi origin
The frontal process of the maxilla
Levator labii superioris alaeque nasi insertion
The skin at the ala of the nose
The skin at the upper lip
Zygomaticus major origin
Zygomatic bone
Zygomaticus major insertion
The skin at the ipsilateral labial commissure and the facial modiolus, in and around the orbicularis oris
Zygomaticus minor origin
The body of zygomatic bone, medial to zygomaticus major muscle
Zygomaticus minor insertion
The skin at the upper lip adjacent to the insertion of the levator labii superioris
Levator anguli oris origin
The body of the canine fossa of the maxilla, usually superior to the root of the maxillary canine
Levator anguli oris insertion
The skin at the ipsilateral labial commissure at the facial modiolus
Depressor anguli oris origin
The body of the inferior border of the mandible
Depressor anguli oris insertion
The skin at the ipsilateral labial commissure at the facial modiolus
Depressor labii inferioris origin
The body of the inferior border of the mandible
Depressor labii inferioris insertion
The skin of the lower lip
Mentalis origin
The anterior mandible near the midline
Mentalis insertion
The skin of the chin
Platysma origin
The skin superficial to the clavicle and shoulder
Platysma insertion
The muscles surrounding the mouth, including the facial modiolus
SCM action
- One muscle contracts: bend to the unilateral side; face and front of the neck rotate to contralateral side
- Both muscles contract: head flexes at neck, and extend at the junction of the neck and skull
- Elevate the thorax during breathing
Trapezius action
Lift the clavicle and scapula (shrugging)
Epicranius action
Raise the eyebrows and scalp (surprise expression)
Orbicularis oculi action
- closing the eyelid
- squinting
Corrugator supercilii action
Draws the skin of the eyebrow medially and inferiorly toward the nose
- vertical wrinkles in the glabella area of the forehead
- horizontal wrinkles at the bridge of the nose
Orbicularis oris action
- pressing lips together (closing)
- tightening and thinning lips (pursing)
- rolling lips inward between the teeth
- pouting and thrusting lips outward (kissing)
Buccinator action
- pulls the labial commissure laterally, shortening and compressing the cheek
- keeps food in the correct position during chewing (assists the muscles of mastication)
- forcefully expells air (trumpet muscle)
- suction
Risorius action
- stretches the lips laterally, widening the mouth
- grimace or stretched out grin
Levator labii superioris action
Elevates the upper lip in a smile
Levator labii superioris alaeque nasi action
Elevates one side of the upper lip towards the nose, dilating the naris (snarling/sneering)
Zygomaticus major action
Elevates the labial commissure of the upper lip, pulling it laterally when a person smiles
Zygomaticus minor action
Elevates the upper lip, assisting in smiling
Levator anguli oris action
Elevates the labial commissure when a person smiles
Depressor anguli oris action
Depresses the labial commissure when a person frowns
Depressor labii inferioris action
Depresses the lower lip, exposing the mandibular incisors
Mentalis action
Raises the chin, wrinkling the skin and protruding the lower lip into a pout
Platysma action
- raises the skin of the neck to form noticeable vertical and horizontal ridges and depressions
- pulls the labial commissure down (grimace of horror or disgust)