Test 2 Flashcards
Facial muscle different compared to other muscules?
muscles attached directly to the skin
Because facial muscles are attached directly to skin it gives them what characteristic?
makes them very mobile
Smiling takes how many muscles?
17
frowning takes how many muscles ?
43
Contraction means? and what does it cause?
the muscle fibers shorten; causes movement
relaxation means? what does it cause?
decrease tension in muscle fibers; does not cause movement
origination part of the muscle ? also called?
also called arise; end of muscle that is attached to the structure that hardly moves
insertion part of the muslce?
end of muscle that is attached to the structure that moves
how do muscles work?
- muscle receives signal from bran (via nerve supply)
- muscle contracts (movement in direction of origin)
general rule about muscles (not always)
muscles are pared and one side will contract while the other will relaxed (facial expressions)
What is the big muscle rule?
compound words (styloglossus) 1st part of the work is point of origin, and 2nd part is point of insertion
ex Stylo-origin-styloid process
Glossus -insertion-tongue
labii means?
lip
anguli
Angle
nasi
nose
bucci
cheek
superioris
upper
inferioris
lower
masticate
chew
what is fascia?
thin layer of connective tissue that covers, supports, or connects muscles or inner organs of the body
what is the sphincter muscle?
a muscle that surrounds and closes an orifice (opening)
Orbiculars oris (origin and insertion)
- Origin- (facial modiolus) encircles mouth with no bony attachments
- insertion- in the skin of the lips at the commissures, upper lip, and philtrum
what is the action of the orbicularis oris?
closing lips (pressing together), tightening and thinning, (pursing) rolling inward between the teeth (grimace), and thrusting outward (pouting/kissing)
Zygomaticus major origin and insertion
Origin- zygomatic bone, lateral to minor
Insertion- skin at the ipsilateral labial commissure at facial modiolus
Action of the Zygomaticus major
elevates labial commissure; smiling