Muscles of the Head, Neck, and Back

lolol pray i pass

what muscle is this

frontalis

what is the action of the frontalis muscle?

raises the eyebrows; wrinkles the skin of the forehead

what is the origin of the frontalis muscle?

occipital bone by way of galea aponeurosis

what is the insertion of the frontalis muscle?

skin of eyebrows and bridge of nose

what muscle is this?

orbicularis oculi

what is the action of the orbicularis oculi?

closes the eye

what is the origin of the orbicularis oculi?

frontal and maxillary bones, margin of orbit

what is the insertion of the orbicularis oculi?

skin around the eye; circles the orbit

what muscle is this?

zygomaticus major

what is the action of the zygomaticus major?

raises lateral corner of mouth upward (smile)

what is the origin of the zygomaticus major?

zygomatic bone

what is the insertion of the zygomaticus major?

skin and muscle about the angle of the mouth

what muscle is this?

orbicularis oris

what is the action of the orbicularis oris?

closes and protrudes the lips (kissing action)

what is the origin of the orbicularis oris?

maxilla and mandible

what is the insertion of the orbicularis oris?

skin surrounding the mouth, lips

what muscle is this?

masseter

what is the action of the masseter?

raises the mandible, prime mover of closing the jaw

what is the origin of the masseter?

zygomatic arch, maxilla

what is the insertion of the masseter?

mandible

what muscle is this?

temporalis

what is the action of the temporalis muscle?

raises the mandible, closing the jaw

what is the origin of the temporalis muscle?

temporal bone

what is the insertion of the temporalis muscle?

coronoid process of the mandible

what muscle is this?

sternocleidomastoid

what is the action of the sternocleidomastoid?

pulls head to one side, pulls head toward chest, or raises sternum

what is the origin of the sternocleidomastoid?

manubrium of the sternum and clavicle

what is the insertion of the sternocleidomastoid?

mastoid process of the temporal bone

what muscle is this

erector spinae

what is the action of the erector spinae?

extends vertebrae and ribs; maintains erect posture

what is the origin of the erector spinae?

sacrum, ilium, lumbar and thoracic vertebrae, ribs

what is the insertion of the erector spinae?

ribs, cervical and thoracic vertebrae

what muscle is this

trapezius

what action is the trapezius

rotates, raises, and pulls the scapula and shoulder downward; extend head, laterally flexes head and neck

what origin is the trapezius

occipital bone, cervical and thoracic vertebra

what insertion is the trapezius

clavicle, acromion, and spinous process of scapula

what muscle is this

latissimus dorsi

what action is the latissimus dorsi

extends, adducts and rotates humerus medially, retracts shoulder

what origin is the latissimus dorsi

sacral, lumbar and lower thoracic vertebrae ; iliac crest and lower ribs

what insertion is the latissimus dorsi

intertubercular groove of humerus