Muscles for midterm Flashcards
Occipitofrontalis
layer of muscle beneath skin of the scalp, pulls skin upwards
Frontalis
wrinkles the forehead, part of the occipitofrontalis
Orbicularis oculi
surrounds the orbit, closes the eyelids
Platysma
just beneath the skin of the anterior neck, may assist in depressing the jaw, mostly makes your skin tight
Zygomaticus Major
elevates the corners of the mouth and aids to create a smile, along with the risorius, zygomaticus minor
Masseter
from zygomatic arch to angle of mandible
most powerful muscle of mastication
Temporalis
a long fan-shaped muscle on the side of the skull which also strongly elevates/closes jaw, retracts the mandible. inserts on the coronoid process
Lateral pterygoid
from deep bones of the skull, the fibers run backward to insert on the neck of the mandible, pulls the neck of mandible forward. Protraction and opens jaw
Medial pterygoid
arises from deep skull, fibers run inferiorly, posteriorly, and laterally to the medial surface of the ramus and angle of mandible. elevates mandible
Tongue
has extrinsic and intrinsics. Know the following extrinsic
Palatoglossus: palate
Styloglossus: styloid process
Hyoglossus: hyoid
Genioglossus: chin
Buccinator
within the cheek, controls food during chewing
Superior rectus
turns eye superiorly
nerve III
Inferior rectus
turns eye inferiorly
nerve III
Medial rectus
turns eye medially
nerve III
Lateral rectus
moves eye laterally
nerve VI
Superior oblique
moves eye down and out
nerve IV
Inferior oblique
moves eye up and out
nerve III
Levator palpebrae
elevates the eyelid
nerve III
works with, or creates the superior tarsal muscle
External Intercostals
Oblique, down, and forward between ribs
Not present medially to costco-chondral junction
draw ribs closer during inspiration/expiration
depends on which part of the thorax is stabilized
Internal Intercostals
oblique, down, backward btwn ribs
not present from vertebrae to angle of ribs
draw ribs closer during insipration/expiration
Innermost Intercostals
deep portions of the internal intercostals
Subcostals
pass nearly vertically over internal surface of angle of ribs, crossing 1-2 spaces, likely depress ribs during expiration
Transversus Throacis
inner chest wall
xiphoid process and inferior sternum, run to costal cartilages 2-6
assists in expiration, depresses costal cartilages
Levator Costae
go from C7-T11 transverse processes. Inserts at external surfaces 1-12 ribs
elevate ribs at joints
