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Flashcards in Histology Deck (29)
1

Oral Cavity

1. vestibule
2. oral cavity proper

2

Vestibule

space b/w lip, cheeks, teeth

3

Oral Cavity Proper

hard and soft palates, tongue, floor of mouth, and entrance to oropharynx

4

3 major paired salivary glands

-parotid
-submandibular
-sublingual
have ducts that open into oral cavity

5

3 types of mucosae that lines oral cavity

1. masticatory mucosa: gingiva and hard palate
SSE Keratinized (SSE parakeratinized) epithelium
2. specialized mucosa: dorsum of tongue, has papillae SSE Keratinized Epithelium
3. lining mucosa: everything else, lips, cheeks, mouth floor, alveolar region, soft palate SSE nonkeratinized epithelium

6

4 types of papillae on tongue

1. Filiform papillae (SSE-K) no taste buds, most numerous
2. Fungiform papillae, may be keratinized, taste buds
3. Circumvallate papillae, taste buds
4. Foliate papillae, taste buds

7

Filiform Papillae

-smallers & most numerous over entire anterior 2/3 of tongue in rows, NO taste buds

8

3 cells in taste buds

1. sensory cells: elongated, predominate, synapse w afferent nerve fiber
2. supporting cells: elongated
3. basal cells: short, stem cells for sensory and supporting cells

9

Taste Buds

-sweet, salt, sour, bitter, umami
-one type of sensory receptor per sensory cell
-buds have mixtures of sensory cell types
-bitter is in back on tongue
-all others are all over
-2000 per tongue
-few are found on roof, post tongue, epiglottis, esophagus, pharynx

10

Serous Cells

in salivary glands
-secrete watery substance with protein, amylase, and lysozyme, have basal basophilia, many granules in apical cytoplasm

11

Mucous Cells

secrete mucus, which is lost during preparation so that apical region looks empty, nucleus typically flattened at base of cell

12

Organization of Salivary Glands

-clusters of cells are organized into acini or alveoli
-myoepithelial cells
-secretions by acini cells is extruded by contraction of myoepithelial cells
-ducts

13

Ducts in Salivary Glands

-intercalated: originate from acini, secrete and absorb, simple cuboidal, small & modifies the secretion
-striated: simple cuboidal to simple columnar cells, striations caused by basal plasma membrane, around size of acinus or larger, modifies secretion

14

Myoepithelial Cells

-elongated contractile cells that surround the epithelial basal lamina

15

Parotid Gland

-purely serous acini

16

Submandibular Gland

mixed, but mostly serous
in mixed glands, mucous cells exist as either purely mucous acini or mixed acini in which serous cells form a cap called serous demilune

17

Sublingual

mixed, mostly mucous

18

Saliva

-mixture from all glands
-1200mL per day
-bicarbonate ions buffer content in oral cavity
-digestive enzymes
-wash away harmful stuff, lubricates, Ca, P, protective film for teeth, medium to food to stim taste buds, abs

19

Whats in Tubular Part of Alimentary Tract

-esophagus, stomach, small intestine, large intestine

20

Tubular: Mucosa

lining epithelium, lamina propria (lymphatic tissue), and muscularis mucosae

21

Tubular: Submucosa

consisting of dense irregular connective tissue

22

Tubular: Muscularis Externa

2-3 layers of smooth muscle

23

Tubular: Serosa

Squamous epith and CT or adventitia consisting of CT

24

Principle Functions of Mucosal Layer

-secretion
-absorption
-protection

25

Principle Functions of Submucosa

blood & lymph vessels, nerve plexus, antigens, occasional glands

26

Principle Functions of Muscularis Externa

-contractions of inner layer compresses and mix contents in lumen, contraction of outer longitudinal layer propels contents by shortening tube
-enteric nervous system (peristalsis)
-form sphincters

27

Rugae

large longitudinal gastric folds that disappear when the stomach is distended

28

Cell division in stomach is restricted to?

isthmus

29

Mammillated folds

small elevations of mucosa only