A&P Exam 3 Anatomy Flashcards
Articulation
Adjustments in the shape of the cavities above the vocal folds (pharynx, oral cavity, and nasal cavity).
Articulators
Structures that effect changes in shape of the cavities above the vocal folds (pharynx, oral cavity, & nasal cavity).
- Can be either mobile or immoble
- Shape vocal tract or provide filter
Source Filter Theory
Voicing is produced by the vocal folds and shaped into sounds by the vocal tract. Changes in the configuration of the vocal tract result in changed resonant characteristics.
Facial Skeleton
Forms framework for organs of mastication, speech, respiration, and muscles of facial expression.
- All bones fused except the mandible
Cranium
Houses and protects brain.
Mandible
Jaw bone. Begins as a paired bone with a symphysis. Fuses early in development to become single bone.
Landmarks of the Mandible
- Mental foramen: small hole on either side
- Alveolar arch: part of the mandible that houses the lower teeth
- Angle: point at which mandible angles upward
- Ramus: flat lateral surface above angle
- Coronoid process: posterior process
- Condylar process: anterior process
- Corpus/Body: lateral mass of bone
Maxillae
- Paired bone that forms upper jaw
- Contributes to formation of roof of mouth, floor and lateral walls of nasal cavity, and floor of orbit
- Each side has a roughly pyramidal shaped body with 4 processes
Landmarks of the Maxillae
- Zygomatic process: attaches to zygomatic bone
- Frontal process: attaches to frontal bone
- Palatine process: attaches to palatine bone (forms posterior of roof of mouth)
- Alveolar process: houses the upper teeth
Nasal bones
Two small oblong plates which form bridge of nose.
- Lie medial to the frontal processes of the maxillae.
- Articulate with frontal bone, maxillae, and other nasal bone.
Palatine bones & landmarks
Small but complex bones that contribute to the floor and lateral wall of the nasal cavity, the posterior 1/4 of the hard palate, and the floor of the orbit.
Includes:
- Horizontal Plate
- Perpendicular Plate
Inferior Nasal Conchae
Small, scroll-like bones that make up the inferior-most aspect of the lateral wall of the nasal cavity.
- Articulates with maxilla, palatine, and ethmoid bones.
- Part of facial skeleton
Vomer
Makes up inferior half of bony nasal septum (separates nasal cavity at midline).
- Articulates with maxillae, palatine, sphenoid, and ethmoid bones
- Anterior border articulates with cartilaginous septum
Zygomatic Bones & Landmarks
Cheekbones. Together with zygomatic process of maxilla and temporal bone form zygomatic arch.
- Roughly quadrilateral body with 3 processes: maxillary, temporal, and frontal
Lacrimal Bones
Part of facial skeleton. Form lateral nasal wall and a small portion of the medial orbit.
Ethmoid Bone
Regarded as a cranial bone, but also contributes to facial skeleton.
- Projects down between orbital plates of frontal bone
- Contributes to walls of orbit and nasal cavity
Landmarks of the Ethmoid Bone
- Crista galli: superior projection
- Perpendicular plate: inferior projection that makes up the superior nasal septum
- Cribform plate: separates cranium from nasal cavity
- Conchae (superior and middle)
- Orbital plate: form medial orbit
Sphenoid bone
Cranial bone located at the base of the skull behind the ethmoid and in front of the foramen magnum.
- Looks like a bat with wings
- Articulates with all bones of the crainum and 3 facial bones
Landmarks of the Sphenoid Bone
- Body: center portion
- Lesser wings: smaller superior wings
- Greater wings: larger inferior wings
- Pterygoid plates: inferior projections
- Medial (AKA hamulus)
- Lateral
Frontal Bone & Landmarks
- Forms anterior part of brain case
- Vertical plate contributes to forehead
- Horizontal plate contributes to roof of orbit and nasal cavities
- Landmarks:
- Nasal portion
- Zygomatic process
- Orbital process
Parietal Bones & Landmarks
Form most of rounded roof of cranium
- Articulates with frontal bone at coronal suture
- Joined together at saggital suture
- Articulates with occipital bone at lamboid suture (in the back)
Occipital Bone & Landmarks
Lower and back portion of cranium. Includes:
- Foramen magnum
- Occipital condyles: articulate with superior facets of C1
Temporal Bones
Paired bones forming most of the lateral base and sides of the brain case. Includes squamous, tympanic, petrous, and mastoid portions.
Temporal bone: Squamous portion
Lateral, anterior, superior aspect of bone. Includes:
- external auditory meatus (EAM): bony part of the ear canal
- zygomatic process: attaches to temporal process of zygomatic bone to form zygomatic arch
Temporal bone: Tympanic portion
Located in front of mastoid process and below squamous & petrous portions. Includes:
- anterior and inferior part of external auditory meatus (EAM)
- styloid process
Temporal bone: Petrous portion
At base of skull. Houses essential organs of hearing (cochlea) and equilibrium (semicircular canals).
Dentition
Highly variable in shape & dimension. Available space is limited by lips and cheeks externally and alveolar processes and (other) teeth internally. Includes:
- Incisors: cutting
- Canines/cuspids: tearing; cuspid = 1 point
- Premolars (bicuspids): bicuspid = 2 points
- Molars: grinding
Parts of a tooth
- Crown: visible 1/3
- covered by enamel (hardest substance in the body
- Neck: transition between crown and root
- Root: remaining 2/3 of tooth
- covered in cementum, which keeps the tooth embedded in the bone
Surfaces of the teeth
- Medial: surface looking along the arch toward the midpoint between the central incisors
- Distal: surface farthest from midpoint between the central incisors
- Buccal: comes in contact with buccal wall (inner cheek)
- Lingual: surface facing the tongue
- Occlusal: contact surface between upper and lower teeth
How many teeth do adults have?
32 (16 upper & 16 lower), including the wisdom teeth
Types of malocclusion
- Class I: normal occlusion; molars line up
- Class II: mandible retracted
- Class III: mandible advanced (underbite)
- Open bite: teeth touch in the back, but not in the front
- Closed bite: molars don’t touch
- Lateral bite: open or closed bite on only one side
Oral cavity
Bounded…
- Anteriorly & laterally by alveolar processes & teeth
- Superiorly by hard & soft palate
- Inferiorly by muscular floor of mouth (under the tongue)
- Posteriorly by anterior faucial pillars (first arch on either side)
Buccal cavity
Highly variable in shape & dimension. Space limited by:
- lips & cheek externally
- alveolar processes & teeth internally
Pharyngeal cavity & sections
Pharynx is a 12 cm long tube that extends from the vocal folds to behind the nasal cavity. Includes:
- Nasopharynx: eustachian tube and pharyngeal tonsils (adenoids)
- Oropharynx: between velum and hyoid bone
- Laryngopharynx: between hyoid and esophagus
Nasal cavity
Bounded:
- sagitally by nasal septum (cartilage & bone)
- anteriorly by nares (nostrils)
- inferiorly by roof of mouth and velum
- posteriorly by nasopharyngeal wall
Nasal conchae are posterior portals connecting nasopharynx and nasal cavities
Obicularis Oris
Principle muscle acting on the lips.
- Oval ring of muscle located within lips
- Is a sphincter muscle (contracts from all sides)
- Completely encircles mouth slit
- Many other muscles insert into it
- Action: closes mouth and puckers lips
Risorius
Highly variable muscle superficial to the buccinator.
- Origin: fascia covering masseter
- Course: forward
- Insert: obicularis oris at corners of mouth
- Action: assist in drawing mouth corner laterally
Buccinator
Principle muscle of the cheek & deepest muscle of the face.
- Origin: pterygomandibular ligament (deep ligament near mandible)
- Course: horizontal & anterior
- Insert: obicularis oris at corners of mouth
- Action:
- compresses lips and cheeks against teeth
- moves food onto grinding surfaces of molars
- constricts oropharynx
Levator labii superioris
(Superior lip elevator)
- Origin: infraorbital margin of maxilla (part of maxilla that contributes to orbit)
- Course: down and in to the upper lip
- Insertion: mid-lateral region of the upper lip
- Action: elevates the lip
Zygomatic minor
- Origin: facial surface of zygomatic bone
- Course: downward
- Insertion: mid-lateral region of upper lip
- Action: elevates upper lip
Levator labii superioris alaeque nasi
(Above the nose, elevates the lip)
- Origin: frontal process of maxilla
- Course: vertically along the lateral margin of the nose
- Insertion: mid-lateral region of upper lip
- Action: elevates the upper lip
Levator Anguli Oris
(Elevates the mouth at the corner)
- Origin: canine fossa of maxilla
- Course: inferior
- Insert: upper and lower lip at corner
- Action: draws corner of mouth up and medially
Zygomatic major
- Origin: surface of zygomatic bone, lateral to zygomatic minor
- Course: inferior & medial
- Insert: obicularis oris and skin at mouth coner
- Action: draws mouth angle superiorly and laterally (think broad smile)
Depressor Labii Inferior
Located beneath the lower lip, just lateral to midline.
- Origin: mandible,lateral to mental tubercles (bumps on chin)
- Course: superior and medial
- Insert: lower lip
- Action: dilates orifice (opens mouth) by pulling the lips down and out
Depressor anguli oris
Superficial to depressor labii inferior
- Origin: mandible, lateral to mental tubercles
- Course: fan-like & superior
- Insert: obicularis oris at mouth corner; some fibers cross into upper lip
- Action: depress the lip angle; helps compress upper lip against the lower lip
Mentalis
- Origin: incisive fossa of mandible (depression by the canines)
- Course: down
- Insert: skin of chin below
- Action: wrinkle chin; evert (turn outward) lower lip
Platysma
- Origin: fascia overlaying pectoralis major
- Course: up
- Insertion: corners of mouth, lower margin of mandible, skin near masseter
- Action: depresses the mandible, opening the oral cavity
Dorsum
Upper surface of tongue. Includes (front to back):
- Tip
- Blade
- Front
- Back
Longitudinal Median Suculus (LMS)
Divides dorsum of tongue into right and left halves.
Foramen cecum
Small pit towards back of tongue
Lingual frenulum
Joins inferior tongue and mandible.
Superior Longitudinal Muscle
Intrinsic muscle of tongue. Thin layer of oblique & longitudinal (run length of tongue) muscle fibers that lies just below mucous membrane of the dorsum.
- Origin: submucous fibrous tissue close to tongue root & fibrous septum
- Course: fans outward and anterior
- Insert: fibrous membrane at edges of tongue and region near apex (tip)
- Action: elevates, assists in retraction, or deviates (moves to one side or the other) the tip
Inferior Longitudinal Muscle
Intrinsic muscle of the tongue. Fibers lie on the underside of tongue, laterally.
- Origin: tongue root, some perhaps from hyoid
- Course: anterior
- Insert: blend with other muscles at apex
- Action: shortens or deviates (moves side to side) the tongue; pulls tip down
Transverse Muscle
Intrinsic muscle of the tongue.
- Origin: median fibrous septum
- Course: lateral
- Insert: submucous fibrous tissue at lateral tongue margins
- Action: narrows tongue
Vertical muscle
Intrinsic muscle of the tongue.
- Origin: base of tongue
- Course: vertically
- Insert: membranous cover
- Action: flattens tongue (pulls tongue down into floor of mouth)
Genioglossus
Extrinsic muscle of the tongue. Bulk of tongue tissue; strongest & largest extrinsic muscle
- Origin: inner mandibular surface near symphysis
- Course: fans up, back, and forward
- Insert: tip and dorsum of tongue, corpus of hyoid
- Action: posterior fibers protrude tongue, anterior fibers retract tongue; together they depress the tongue
Hyoglossus
Extrinsic muscle of the tongue.
- Origin: body & greater horn of hyoid bone
- Course: vertically, diverging slightly
- Insert: lateral submucous tissue of posterior 1/2 of tongue
- Action: pulls sides of tongue down
Styloglossus
Extrinsic muscle of the tongue.
- Origin: styloid process of temporal bone
- Course: radiates inferiorly & anteriorly
- Insert: sides of tongue near dorsum
- Action: draw tongue superiorly & posteriorly
Masseter
Most powerful muscle for mastication. Thick, flat muscle covering lateral aspect of mandibular ramus.
- Origin: zygomatic arch
- Course: inferior & posterior
- Insert: angle & lateral surface of ramus
- Action: closes jaw
Temporalis
Broad, thin muscle on side of skull, over temporal bone.
- Origin: temporal fossa of temporal and parietal bones
- Course: fibers converge downward and pass under zygomatic arch
- Insert: coronoid process & ramus of mandible
- Action: elevation & retraction
Medial (Internal) Pterygoid
Thick, quadrilateral muscle.
- Origin: medial pterygoid plate & fossa of sphenoid bone
- Course: inferior, posterior, & lateral
- Insert: mandibular ramus
- Action: elevation
Mandibular sling
Formed by medial pterygoid & masseter. Straps mandible to skull.
Lateral (External) Pterygoid
- Origin: greater wing of sphenoid & lateral pterygoid plate
- Course: horizontal & posterior
- Insert: condyle of mandible
- Action: protude mandible; unilateral contraction produces grinding action
Digastric
Depressor of the mandible (or, elevator of the larynx)
- Anterior belly
- Origin: inner surface of mandible, near midline
- Course: inferior and posterior
- Insert: lesser horn of hyoid
- Action: pulls hyoid forward
- Posterior belly
- Origin: mastoid process of temporal bone
- Insert: lesser horn of hyoid
- Attach to one another via intermediate tendon
- Action: pulls hyoid back
- Together they depress the mandible (if the hyoid remains fixed)
Mylohyoid
Fanlike fibers that form muscular floor of mouth
- Origin: inner surface of mandible from mental symphysis (midline) to last molar
- Course: inferior and medial
- Insert: with fibers from other side at midline raphe
- posterior fibers onto body of hyoid bone
- Action
- If mandible is fixed, elevate hyoid bone
- If hyoid is fixed, depresses mandible
Geniohyoid
Paried muscle superior to mylohyoid
- Origin: lower part of mental symphysis
- Course: posterior and inferior
- Insert: body of hyoid bone
- Action:
- With mandible fixed, raises hyoid bone superiorly and anteriorly
- With hyoid fixed, depresses mandible
Hard palate
Formed by palatine process of maxilla (anteriorly) and palatine bones (posteriorly).
Soft Palate
AKA velum
- Muscular valve that modifies communication between oral & nasal cavities
- Usually lowered, leaving velopharyngeal port open & producing nasal sounds
- When raised, closes off velopharyngeal port for oral sounds & swallowing
- Attached to hard palate via palatal aponeurosis
Coronal Movement of the Velopharyngeal Mechanism
Anterior to posterior (front to back) movement of the velum to meet the posterior pharyngeal wall.
Sagittal Movement of the Velopharyngeal Mechanism
Lateral movement of the sides of the pharynx.
Circular Movement of the Velopharyngeal Mechanism
Posterior pharyngeal wall moves anteriorly (forward).
Passavant’s ridge
Extra padding on the posterior pharyngeal wall. Requires less movement of the velopharyngeal mechanism to close velopharyngeal port.
Levator veli palatini
Forms bulk of soft palate.
- Origin: petrous portion of temporal bone & medial aspect of eustachian tube
- Course: inferior, medial, & anterior
- Insert: palatal aponeurosis of soft palate (lateral to uvula)
- Action: pull soft palate superiorly & posteriorly to posterior pharyngeal wall (contributes to coronal movement)
Musculus Uvulae
- Origin: area of posterior nasal spine/septum
- Course: along upper surface of soft palate
- Insert: mucous membrane cover of the velum
- Action: shortens the soft palate (moves it anteriorly)
Tensor vili palatini
- Origin: sphenoid spine & lateral wall of eustachian tube
- Course: inferiorly, winding around hamulus, then coursing medially towards palate
- Insert: expands into palatal aponeurosis
- Action: dilates eustachian tube; may elevate & provide tension to soft palate
Palatoglossus
Extrinsic muscle of the tongue & muscle of the soft palate. AKA glossopalatine; both structures are movable.
- Anterior faucial pillar (front arch)
- Origin: anterolateral palatal aponeurosis
- Course: down
- Insert: sides of posterior tongue
- Action: elevates the tongue or depresses the soft palate
Palatopharyngeus
Posterior faucial pillar (back arch)
- Origin: anterior hard palate (anterior fibers) & midline of soft palate (posterior fibers)
- Course: inferiorly & laterally
- Insert: posterior margin of thyroid cartilage
- Action: narrows pharynx; lowers soft palate
Superior pharyngeal constrictor
Weakest, but most complex of the 3 pharyngeal muscles. Includes 4 muscle bundles & forms nasopharyngeal & upper oropharyngeal walls.
- Origin: pterygomandibular raphe
- Course: posteriorly
- Insert: midline pharyngeal raphe (posterior midline)
- Action: pulls pharyngeal wall forward, constricts pharyngeal diameter
Stylopharyngeus
Elevates & opens pharynx during deglutition.
- Origin: styloid process
- Course: down & medial, between superior & middle constrictors
- Insert: pharynx & posterior thyroid cartilage
- Action: elevates larynx & elevates/opens pharynx (during swallowing)
Middle pharyngeal constrictor
- Origin: hyoid bone
- Coourse: radiating posteriorly, superiorly, and then medially
- Insert: midline pharyngeal raphe
- Action: modify diameter of pharynx
Inferior pharyngeal constrictor (aka cricopharyngeus)
Thickest and strongest constrictor
- Origin: most from thyroid cartilage
- Course: radiating posteriorly and then medially
- Insert: midline pharyngeal raphe
- Action: constricts superior opening of esophagus, reduces diameter of lower pharynx
Salpingopharyngeus
- Origin: inferoposterior surface of eustachian tube
- Course: posteriorly
- Insertion: lateral walls of pharynx intermixed with palatopharyngeus
- Action: elevation of pharynx, movement of eustachian tube (popping of ears)
