Muscles week 1 Flashcards
muscles
Specialized cells with the property of contractility
name of a muscle cell
myoblast
basis of motion
change from chemical to mechanical energy by enzymatic cleavage of ATP (adenosine triphosphate - stores energy in muscles)
3 types of muscles
Skeletal, Smooth, & Cardiac
skeletal
Voluntary…muscles controlled by central & peripheral nervous system (pharynx, esophagus, tongue, facial expression & mastication)
smooth
Involuntary…under control of autonomic nervous system (located in organs, glands & lining of blood vessels)
cardiac
involuntary (wall & major veins of heart)
cardiac and skeletal are considered
striated Muscle cells appear to be “banded”
Muscle cell is like a fiber
perimysium
covers each muscle fiber
epimysium
covers the entire muscle
myofibril
Any of the threadlike fibrils that make up the contractile part of a striated muscle fiber and are made up chiefly of actin and myosin filaments.
each myofibril contains
actin & myosin (proteins) which cause the contraction vital to muscle function
each muscle is a
bundle of muscle fibers, (myofibrils composed of myofilaments) each of which is
a long multinucleated cell.
myoblast
single mononucleated cells
myotube
myoblasts fused together to form multinucleated fiber during development
myofibril
a muscle fibril, one of the slender threads of a muscle fiber, composed of numerous myofilaments
origin
End of the muscle that is attached to the
least movable structure…(Home-Base)
insertion
Other end of muscle attached to
more moveable structure
action
Movement accomplished when the muscle fibers contract
Sternocleidomastoid
Origin: sternum & clavicle
Insertion: Mastoid process of Temporal Bone
Action: Flexes & rotates head
Divides the neck into anterior & posterior cervical triangles
*Innervation: 11th cranial/accessory nerve
Trapezius
Origin: occipital bone & midline of cervical/thoracic regions
Insertion: clavicle & scalpula
Action: Raises or lowers clavicle & scalpula
shoulders: “shrug”
*Innervation: 11th cranial/Accessory nerve
muscles of facial expression are
paired located superficial fascia of facial tissue
where do all muscles of facial expression originated from
Bone & insert into skin tissue
epicranial muscle
scalp region for facial expression
2 bellies of the epicranial muscle
frontal and occipital Connected by a scalpal tendon
Epicranial Aponeurosis
Muscle & tendon are one of the layers that forms the scalp
occipital belly of epicranial muscle
Origin: occipital & temporal bone,
Insert: epicranial aponeurosis
frontal belly of epicranial muscle
Origin: Epicranial aponeurosis,
Insert: eyebrow & root of nose
action: raise the eyebrows and scalp
Orbicularis oculi
encircles eye
Origin: orbital rim, nasal process of frontal bone, frontal process of maxilla
Insert: lateral skin of eye, some completely encircle eye
Action: closes eye, squints eye,
“crows feet”
Corrugator supercilii
Origin: on frontal bone in the supraorbital region
Insert: skin of eyebrow
Action: Draws skin tissue medially & inferiorly, causes wrinkles in forehead - Frowns
Orbicularis Oris
Origin encircles mouth
Inserts in skin at angle of mouth & philtrum of lip
Action: Closes lips, tightening: pursing, rolling in:+ grimace, thrusting out: pouting/kissing
This one makes it tough to scale lower ant. teeth!
Buccinator
Origin :
alveolar process &
pterygomandibular raphe
fibrous structure w/runs from hamulus to posterior portion of mylohyoid line
Inserts angle of mouth
(both horizontal and vertical fibers)
Action: pushes food back forms anterior portion of cheek & suction for suckling
Risorius
Origin: fascia of masseter muscle
Inserts: angle of mouth
Action: Widens mouth when smiling WIDELY, works w/ platysma = Grimace
Levator Labii Superioris
Origin: infraorbital rim of maxilla
Inserts: upper lip
Action?
elevates upper lip
Levator Labii Superioris Alaeque Nasi
Origin: frontal process of maxilla
Insert: ala & upper lip
Action: elevates both & dilates nostrils = sneer
Levator Anguli Oris located deep to the zygomaticus mus.
Origin: canine fossa
Inserts: angle of mouth ACTION?
elevates angle of mouth
zygomaticus major
Origin: zygomatic bone
Inserts: in angle of mouth positioned lateral to minor
function: elevate upper lip
zygomaticus minor
Origin: zygomatic bone
Insert: upper lip
function: assist with smile
Depressor anguli oris
Origin: lower mandible
Insert: in angle of mouth
Action: depresses the angle of the mouth = frown
Depressor Labii Inferioris
Origin: lower border of Mand.
Inserts: in lower lip
Action: frowns (depresses lower lip, exposing mand. incisors)
mentalis
A short, thick muscle
Origin: mandible near midline
Insert: skin of chin
Action: ?
Raises chin, protrudes lower lip = displaced denture
platysma
Runs from neck all the way to the mouth
Origin: skin superficial to clavicle & shoulder
Insert: lower border of mandible & muscles around mouth
Action: ?
Raises skin of neck & pulls corner of mouth down
five muscles that help you smile
Levator labii superioris:Raises upper lip
Levator anguli oris:Elevates Commisure(s)
Zygomaticus major & minor Raises upper lip
Risorous (#5)widens mouth when smiling(related more to a grimace)
muscle of mastication
Four pairs of muscles attached to the mandible:
Masseter
Temporalis
Medial Pterygoid
Lateral Pterygoid
muscle of mastication
Responsible for all movements of mandible: LIST:
*Depression & elevation
(Opening/closing jaws)
*Bringing lower jaw forward or backward
(Protrusion & retraction)
*Shifting lower jaw side to side
(Lateral deviation)
Which nerve innervates the Muscles of Mastication & TMJ muscles?
5th cranial nerve: Trigeminal (mandibular division)
Masseter location
Most superficially located muscles of mastication One of the strongest
2 bellies: Both Superficial & Deep head
masseter
Origin:
Zygomatic arch
Superficial Head
Ant. 2/3 of lower border of Zygomatic Arch
Deep Head
Post. 1/3 & entire medial surface of Zygomatic arch
Insertion:
Superficial head
lateral surface of angle of mandible
Deep Head
ramus above angle of mandible
Action ?
Elevation of mandible (closing jaw)
pterygoid medial
Origin: Pterygoid fossa of sphenoid
Insert: at angle of mandible, medial surface
Action: elevation of mandible closing of jaw
pterygoid lateral
Origin: greater wing & lateral pterygoid plate of sphenoid
Insert: in pterygoid fovea of mandible
action: shift jaw to opposite side and protrusion of jaw
temporalis
Origin:
temporal fossa & infratemporal crest
Insertion: coronoid process
Action?
Elevation & retraction of mandible (raises & draws mandible backward)
hyoid bone
Horseshoe-shaped
Suspended bone
Muscular & ligamentaryattachments only
Hyoid muscles suprahyoid
Digastric
Anterior belly (A)
Posterior belly (P)
Mylohyoid (A)
Geniohyoid (A)
Stylohyoid (P)
hyoid muscles infrahyoid
Sternothyroid
Sternohyoid
Thyrohyoid
Omohyoid
Suprahyoid muscles
Superficial position in neck tissue
anterior or posterior group
All attached in some way to hyoid bone
Anterior Suprahyoid muscle group only
Action: Depress the mandible & opens jaw during mastication
Anterior & Posterior Suprahyoid muscle groups together:
Action: Elevation of hyoid bone & larynx-during swallowing
Suprahyoid muscle digastric posterior belly
O: Posterior belly: mastoid notch
I: Posterior belly: intermediate tendon
Suprahyoid muscle digastric anterior belly
O: Anterior belly - intermediate tendon
I: Anterior belly - medial surface of mandible
Q: What do the 2 bellies join by?
A: Intermediate tendon
Suprahyoid Muscle: Digastric-Anterior & Posterior Belly
Back to Front with a tendon in the middle!
Suprahyoid Muscle: Digastric
Action anterior belly:
depress mandible opening jaw (main action)
Action anterior & posterior belly: elevate hyoid & larynx during swallowing
Suprahyoid Muscle: Mylohyoid
Origin:
mylohyoid line of mandible
R & L sides unite medially, forming the floor of mouth
Inserts: Posterior portion on the body of hyoid
Action:
Depress mandible & elevates hyoid bone/ larynx
Forms floor of mouth & helps elevate tongue
Suprahyoid Muscle: Stylohyoid
Origin: styloid process of temporal bone
Insertion: body of hyoid bone
Action?
Elevation of hyoid & larynx during allowing
Suprahyoid Muscle: Geniohyoid
Origin: genial tubercles of mandible
Insertion: body of hyoid bone
Action
Elevate the hyoid bone & larynx
Contraction of this muscles also causes the mandible to depress
Infrahyoid Muscles
Attached in some way to the hyoid bone
Located inferior to the hyoid bone
Infrahyoid muscles:
Actions:
1. Most depress the hyoid bone
2. Other specific actions to be discussed
Sternothyroid
Origin: posterior surface of sternum
Insertion: inserts
on thyroid cartilage
Action?
depresses the thyroid cartilage & larynx
Sternohyoid
Origin: posterior & superior surfaces of sternum
Insert: on body of hyoid
Action?
Depresses hyoid bone
Omohyoid inferior belly
origin: scapula
insertion: tendon to superior belly
Action: depress hyoid
Omohyoid superior belly
origin: tendon
insertion: body
of hyoid
Action: depress hyoid
Thyrohyoid
Origin: thyroid cartilage
Insert: on body & greater cornu of hyoid bone
Action:
Depresses the hyoid bone & raises the thyroid cartilage & larynx
muscles of tongue
intrinsic tongue, extrinsic, innervated
Intrinsic tongue muscles
located entirely inside the tongue
(Changes shape of tongue~Shape-shifters)
Extrinsic tongue muscles
genioglossus, styloglossus & hyoglossus
(Moves & anchors tongue to mandible, styloid process & hyoid bone)
innervated tongue muscles
Innervated by hypoglossal or 12th cranial nerve
tongue dorsal surface
specialized epithelium
Filiform, fungiform, foliate & circumvallate papilla
tongue ventral surface
lining mucosa
nonkeratinized epithelium
Genioglossal
Origin: genial tubercle
Inserts: on hyoid bone & in the tongue from its base almost to apex
Action
Protrudes the tongue out of the oral cavity or depress parts of the tongue
styloglossal
Origin: styloid process of temporal bone
Insert: lateral surface of the tongue, its apex & at border of body & base
Action
Retracts the tongue superiorily & posteriorly
Hyoglossus
Origin: greater cornu & part of body of hyoid
Insert: lateral surface of the body of tongue
Action:
Depresses the tongue
Muscles of the Pharynx
Part of both the respiratory & digestive tract
3 portions: Nasopharynx, Oropharynx & Laryngopharynx
Muscles involved in speaking, swallowing & middle ear function
Stylopharyngeus, pharyngeal constrictors & soft palate muscles
Stylopharyngeus Muscle
Origin: styloid process of temporal bone
Insert: into the lateral & posterior pharyngeal walls
Action?
Elevates & widens the pharynx…
Upon swallowing food
Pharyngeal constrictor muscles 3 pairs
superior, middle, inferior
Superior Pharyngeal Constrictor
Origin: hamulus, mandible & pterygomandibular raphe
insert: median pharyngeal raphe
Middle Pharyngeal Constrictor
Origin: hyoid bone & Stylohyoid ligament
insert: median pharyngeal raphe
Inferior Pharyngeal Constrictor
Origin: thyroid & cricoid cartilage of larynx
insert: median pharyngeal raphe
Pharyngeal Constrictor Muscles
Action: all raise the pharynx & larynx & help drive food inferiorly into the esophagus during swallowing
Pharyngeal Constrictor Muscles: superior origin
Pterygomandibular Raphe, Hamulus & mandible
Pharyngeal Constrictor Muscles: middle origin
Hyoid bone & stylohyoid ligament
Pharyngeal Constrictor Muscles: Inferior origin
Thyriod & Cricoid cartilage of larynx
Muscles of Soft Palate
Soft palate forms the nonbony posterior portion of the roof of the mouth (Oropharynx)
Connects laterally with the tongue
Muscles involved in speaking & swallowing.
4 paired & 1 singular muscle …?
(Uvula)
Palatoglossus
Anterior pillar or arch
Palatopharyngeus
Posterior pillar or arch
Levator Veli Palatine
Raises soft palate to close off nasopharynx during speech & swallowing
Tensor Veli Palatini
Stiffens soft palate
Uvula
Helps close off nasopharynx
Palatoglossus
origin: median palatine raphe
(Forms anterior pillar)
insert: lateral surface of tongue
Action: elevates base of the tongue, depresses soft palate toward tongue
Soft Palate Muscle: Palatopharyngeus
Origin: soft palate (Forms posterior pillar)
Insert: walls of laryngopharynx & thyroid cartilage
Action: moves palate posterio-inferiorly & pharynx antero-superiorly
Helps close off the nasopharynx during swallowing
Soft palate: Uvula
adapts to posterior pharyngeal wall
Origin/Insertion: tissue projection that hangs inferiorly from the posterior soft palate
Action: Contraction of this muscle will shorten & broaden it to change the contour of the soft palate.
Helps close off the nasopharynx during swallowing.
Soft Palate: Levator veli palatini
Origin: temporal bone
Insert: median palatine raphe
Action: raises soft palate, brings it in contact with posterior pharyngeal wall
Helps close off the nasopharynx during swallowing
Soft Palate: Tensor veli palatini
Origin: auditory tube & inferior sfc. of sphenoid
Insert : median palatine raphe
Action?
Tenses & slightly lowers the soft palate
