4 Regional Histology of Oral Mucosa Flashcards
what separates the oral (anterior 2/3) and oropharyngeal (posterior 1/3) cavities
the sulcus terminalis (V-shaped goove) and palatoglossal fold/arch
what is the function of the tongue
Articulation of speech, manipulating food into the oropharynx during deglutition, involved with mastication and taste
what are the 3 parts of the tongue
- Root (posterior 1/3)
- Body (anterior 2/3, mobile)
- Apex (anterior 2/3, mobile)
what part of the tongue is mobile
the anterior 2/3
T/F
the dorsal surface of the anterior 2/3 of the tongue comes from ECTOderm
TRUE
T/F
the ventral surface of the anterior 2/3 of the tongue comes from ECTOderm
FALSE
ENDODERM!! (as is the dorsal surface of the oropharyngeal region posterior 1/3 of the tongue too)
which surface of tongue faces palate
dorsal
ventral faces floor of mouth
is specialized mucosa on the dorsal or ventral surface of the ant 2/3 of tongue
dorsal. SSK with lingual papilla
what type of mucosa does the ventral surface of the ant 2/3 of tongue have
LINING mucosa - very think SSNK and NO taste buds.
can see deep lingual vein
what type of glands are by the apex of tongue
MIXED minor salivary glands
what is a frenulum
mucosal fold connecting tongue to floor of mouth
what type of epi is the dorsal surface of the posterior 1/3 of tongue
SSNK - cobblestone appearance
what GL is the dorsal surface of the post 1/3 of tongue
ENDO
what two regions of the tongue have lining mucosa, endoderm GL, and SSNK
ventral surface of ANT 2/3 and dorsal surface of POST 1/3
what region of the tongue has SSK, ECTO GL, and Specialized mucosa with lingual papilla
dorsal surface of ANT 2/3
where can you find lingual papillae
dorsum of ant 2/3 tongue
what are lingual papillae
- Mucosal irregularities and elevations
- Specialized mucosa
- Associated with taste buds
what is the origin of the thyroid gland
foramen cecum – anything ant to it is considered the ant 2/3 of tongue
4 types of papillae
filiform
fungiform
circumvallate
foliate
what papillae are arranged in V-shaped rows parallel to sulcus terminalis
Filiform
what papillae are observe as pink or red spots, scattered among filiform papillae; more numerous at apex of tongue
fungiform
what papillae are v shaped arranged and directly anterior to sulcus terminalis
circumvallate
what papillae are Transverse parallel ridges anterior lateral to circumvallate papillae (organized at right angle to long axis of tongue)
foliate
what papillae are on the side of the tongue
foliate
what are the huge papillae
circumvallate
what papillae would you find a bunch of at apex of tongue
fungiform
which papillae has NO TASTE BUDS
filiform
what type of epi are filiform
Conical, elongated projections with highly developed SSK epithelium
what papillae serve a mechanical role
filiform -> GSA lingual branch of V3
touch, vibration and pressure
which papillae on a slide have their tips point posteriorly
filiform
kinda looks like hair blowing in wind on a guy
what papillae are mushroom shaped
fungiform
what papillae are Scattered amongst and project above filiform papillae
fungiform
T/F
fungiform are Highly vascular CT core that projects to the base of the very thin SSK gives red appearance (similar feature to vermillion zone)
TRUE
what innervates taste buds
branch of facial -> chorda tympani (SVA) and a small contribution from lingual branch of glossopharyngeal
what papillae Consist of parallel low ridges (same height) separated by deep mucosal clefts and are aligned in right angles to the long axis of the tongue
foliate
T/F: circumvallate are Composed of thick SSNK with numerous taste buds along the lateral surface
FALSE
FOLIATE ARE!!
what types of glands are in the CT in foliate
serous glands –> need to start breaking down food!
what papillae are covered with SSK and very thin keratin layer
circumvallate
how can you tell the difference bw circumvallate and fungiform
Location of taste buds distinguishes vallate from fungiform papillae
vallate -> Taste buds line the lateral walls within the invaginated trenches
fungiform -> located at the apical interface of the epithelium and CT
what papillae are surrounded by deep moat-like circular trenches (clefts)
circumvallate papillae
what papillae contain taste buds
-Present on fungiform, foliate and circumvallate papillae
-Oval, pale-staining bodies that extend through the thickness of the epithelium
what are the 3 principle cell types on taste buds
- Neuroepithelial (sensory cell)
- Supporting cell
- Basal cell (stem cell)
where are chemoreceptors located in taste buds
Chemoreceptors located along microvilli within taste pore
* different receptors/ion channels required to interpret sweet, salty, bitter, sour and umami
* Every taste bud is capable of detecting each taste modality
where can you find free taste buds
Free taste buds scattered throughout soft palate, posterior 1/3 of tongue, palate, epiglottis and even the larynx
what does the sulcus terminalis mark
Marks point of fusion between 1st arch and 3rd arches
what does the foramen cecum mark
represents site of origin for thyroid gland –visible in adult
* Thyroid gland: develops from the endoderm in floor of pharynx (between PA 1 and PA 3) demarcated by the
foramen cecum and migrates to final location
what does PA 1 form
ectodermal mucosa of ant 2/3
what does PA 3 form
endodermal mucosa of psot 1/3
what does PA 4 form
forms endodermal mucosa for root of tongue (minor contribution) and epiglottis
-Lateral lingual swellings (distal tongue buds) –bilateral structures
-Median tongue bud (Tuberculum impar ) -central structure between lateral lingual swellings
WHAT ARCH
PA 1
Hypopharyngeal (Hypobranchial) eminence (rostral) —midline structure extending from arches 3rd and 4th
WHAT ARCH
PA 3
Hypopharyngeal (Hypobranchial) eminence (distal) AND Epiglottic swelling (4th)
WHAT ARCH
PA 4
T/F
region of 2nd pharyngeal arch= copula and DOES contribute to tongue region. The 2nd arch is overgrown by hypopharyngeal (hypobranchial) eminence 3rd
FALSE
region of 2nd pharyngeal arch= copula and DOESNT contribute to tongue region. The 2nd arch is overgrown by hypopharyngeal (hypobranchial) eminence 3rd
what n is associated with PA 4
Vagus (CN X) –GSA and SVA (taste)
*Epiglottis (oral side) Mucosa and taste buds of epiglottis and small portion of posterior 1/3 mucosa
what n is associated with PA 3
Glossopharyngeal (CN IX) –GSA and SVA
*Posterior 1/3 Mucosa and taste buds of posterior1/3 tongue & taste buds circumvallate papillae
what n is associated with PA 2
Copula overgrown and becomes embedded in anterior 2/3 of tongue
* Anterior 2/3-taste
* Chorda tympani (CN VII)- SVA
T/F
Hypoglossal (CN XII) –all skeletal muscles EXCEPT palatoglossus muscle (PA 4) (extrinsic)
Tongue contains intrinsic (change shape) and extrinsic (position) muscles
TRUE
what is Pseudomembranous candidiasis (thrush)
candida albicans. can exist in 3 phases: yeast, pseudophyphae and hyphae
Hyphae are seen in the parakeratinized layer of the epithelium as a superficial infection.
Typically, the epithelium is hyperplastic and hyperparakeratinized with leukocytes
what provides motor to palatoglossus ms
pharyngeal plexus - CN X
**ALL other skeletal ms of tongue are3 hypoglossal XII
what are PA 2 developmental precursors and adult structures
copula (no adult structure)
what are PA 1 developmental precursors and adult structures
tuberculum impar and lateral lingual swellings
adult: none and mucosa of ant 2/3
what are PA 4 developmental precursors and adult structures
hypobranchial eminence/epiglottic swelling
adult: mucosa of root of tongue/epiglottis
