Histology of the Oronasal Cavity (Dennis) Flashcards
Describe and Identify Respiratory Epithelium
pseudostratified, columnar ciliated epithelium
contains goblet cells and nonciliated basal stem cells
lamina propria is rich in vaculature and capillary loops
Describe the three regions of the nasal cavity
- nasal vestibule
- respiratory region
- olfactory region
- inside nostriles, lined by skin
- inferior 2/3 lined with resp. mucosa
- upper 1/3, lined by olfactory mucosa
function to regulate Temp. and humidity of air, large surface area due to turbinate bones
Describe the paranasal sinuses
- air-filled spaces in bones, lined with resp. epithelium
- communicate with nasal cavities via narrow openings onto resp. mucosa
- easily infected by viruses
the nasal vestibule is comprised of this type of tissue
keratinized stratified sqaumous epithelium (skin)
The respiratory area of the nasal cavity is composed of this type of tissue
pseudostratified columnar ciliated epithelium
What are the features of the Olfactory Mucosa?
what is the HALLMARK FEATURE?
contains receptors for sense of smell
pseudostratified ciliated columnar epithelium
olfactory glands for dissolving odorant molecules
DRAMATICALLY THICKER AND LACKING GOBLET CELLS, thin basement membrane
don’t need goblet cells because they have olfactory glands that secrete serous fluids
describe and identify the olfactory receptor cells
single dendritic process
specialized, nonmotile cilia w/ odorant receptors
ligand binding causes signals to be sent to olfactory bulb
basal cells-olfactory receptor and supporting cells
brush cells-ciliated columnar cells, contacts CN V
supporting cells-mechanical and metabolic support to olfactory receptors
Describe the oral cavity tissues
- lined by mucous membrane, stratified squamous with varying keratinization levels
- lining, masticatory, and specialized mucosas
- supported by lamina propria (papillary layer and dense layer)
- submucosal layer is present depending on location
Describe the masticatory mucosa
- on hard palate, ginigva, dorsal tongue
- keratinized or parakeratinized stratified squamous epithelium
- superificial cells do not lose cytoplasm
- nuceli are pyknotic and remain until exfoliated
- rete and papillae
- thin or absent submucosa
describe the lining mucosa
- lips, cheeks, alveolar mucosal surface, floor of mouth, inferior surface of tongue and soft palate
- fewer rete and CT
- disting submucosa
- Nonkeratinized stratified sqaumous epithleium, with parakeratinized locations
- stratum basale, spinosum, and superficiale
Describe specialized mucosa
- taste
- dorsal tongue
- tongue consists of masticatory and specialized mucosa (keratinized squamous epithelium)
- lingual papilla are keratinized epithelium within lamina propria, some of which are assocaited with taste buds
Describe and identify filiform papillae
Move fod toward pharynx for swallowing
dorsal tongue “velvety” texture. ew.
cone shape
no taste buds
describe and identify foliate papilla
vertical ridges on lateral surface of tongue in posterior region
taste
Describe and identify Fungiform Papillae
Dorsal surface of tongue, fewer in number
taste
Describe and identify circumvallate papillae
7-15 raised mushroom shaped structrues anterior to sulcus terminalis
sunken appearance surrounded by trench
hundreds of taste buds present
Describe and identify taste buds
barrel shaped organs, perceive food molecules
30-80 spindle shaped cells extending from basement membrane
sweet, salty, sour, bitter, umami
each taste bud can discern all five tastes but concentrate on 2/5
Describe these parts of the taste bud:
neuroepithelial cells
supporting cells
basal cells
neuroepithelial cells: elongated cells extending from the basal lamina to the taste pore, synapse with CN VII, IX, X
supporting cells: elongated cells from basal lamina to taste pore, do not synapse with nerve cells
basal cells: located on basal portion of taste bud, near basal lamina, stem cells for other two types
Describe and identify tonsils
large mass of lymphoid tissue, located in mucosa of posterior oral cavity, oropharynx, and nasopharynx
protect against inhaled or injested substances
partially encapsulated
Describe and identigy palatine tonsils
nonkeratinized stratified sqaumous epithelium
10-20 tonsillar crypts
lots of lymphocytes
dense CT acts as a partial capsule
Describe and identify dentin
composed of calcified organic matrix, similar to bone
contains calcium hydroxyapatite crystals in matrix
dentinal tubules radiate to periphery of dentin
Describe and identify enamel
translucent substances made of enamel rods of calcium hydroxyapatite
cemented together by interprismatic material
Describe and identify cementum
amorphous calcified tissue (calcium hydroxyapatite) into which the PDL is anchored
covers dentin in the root
thicker towards apex of root
anything below the gumline is surrounded in cementum
Describe and identify pulp
loose mesencymal CT
collagen fibers and fibroblasts, mesenchymal stem cells
highly vascular, well innervated
nutrition to dentin, can form reactive dentin due to chronic injury
Describe and identify the perichondrium
describe how a tooth falls out
cementum, peridontal L., alveolar bone, gingiva
peridontal L. inserts onto cementum and alveolar bone that lines the alveolus, comprised of collagen fibers
osteoclasts dissolve all the cementum and root and PDL detaches and tooth comes out
