GI tract I

Question 1

define upper vs lower GI tracts

Answer 1

upper- mouth, esophagus, stomach

lower- small and large intestine

Question 2

what epithelium composes the external lip?

Answer 2

stratified squamous keratinized with hair follicles and sebaceous glands

Question 3

what epithelium composes the vermillion border?

Answer 3

stratified squamous keratinized, no hair follicles or sebaceous glands

Question 4

what epithelium composes the internal lip?

Answer 4

stratified squamous non-keratinized

Question 5

what gives the vermillion border its red appearance?

Answer 5

high dermal papillae allow for capillaries to be very close to the skin

Question 6

where are minor salivary glands located in the internal lip?

Answer 6

submucosal layer

Question 7

what epithelium composes the oral cavity?

Answer 7

stratified squamous non-keratinized

Question 8

what is perakeratosis?

Answer 8

nuclei retained to the top layer

Question 9

why is it useful to know that the inferior oral mucosa is thinner than the rest?

Answer 9

good site for drug absorption

Question 10

which tissue types in the mouth have different epithelium? different lamina propria?

Answer 10

gingiva and hard palate are keratinized d/t high mechanical stress; dense CT in lamina propria

Question 11

what is the composition of the lamina propria for most of the mouth?

Answer 11

loose CT

Question 12

where are the minor salivary glands of the oral cavity located?

Answer 12

submucosa

Question 13

what layer is notably absent in the gingiva and hard palate?

Answer 13

submucosa- in these layers, the mucosa is attached directly to the underlying periosteum

Question 14

describe the skeletal mm configuration of the tongue

Answer 14

3 planes of skeletal mm, extrinsic and intrinsic layers, adipose tissue interspersed

Question 15

describe the ventral surface of the tongue

Answer 15

stratified squamous non-keratinized epithelium, lamina propria present, submucosa absent

Question 16

describe the dorsal surface of the tongue

Answer 16

stratified squamous keratinized, has sulcus terminalis (V-shaped)

Question 17

what lies at the point of the sulcus terminals?

Answer 17

foramen cecum

Question 18

what are the lingual papillae?

Answer 18

broad term for elevations that contain taste buds, many types

Question 19

describe filliform papillae

Answer 19

most numerous and smallest
anterior tongue
highly keratinized 
no taste buds
primary role is pushing food back

Question 20

describe fungiform papillae

Answer 20

mushroom shape
thin keratin
taste buds dorsally

Question 21

describe circumvallate papillae

Answer 21

8-12 total anterior to sulcus terminalis
slightly keratinized
taste buds laterally
house von ebner’s glands

Question 22

what are von ebner’s glands?

Answer 22

lingual salivary glands

Question 23

describe foliate papillae

Answer 23

poorly developed in humans
non-keratinized
on lateral tongue
taste buds laterally
house von ebner's glands

Question 24

where are taste buds located?

Answer 24

lingual papillae: fungiform, circumvallate and foliate; soft palate, pharynx, epiglottis

Question 25

describe taste bud structure

Answer 25

taste pore opens at apex

Question 26

what are the 3 general cell types in taste buds?

Answer 26

neuroepithelial, supporting cells, basal cells

Question 27

which CNs supply taste?

Answer 27

CN VII, IX, X

Question 28

what supplies general sensation to the tongue?

Answer 28

CN V

Question 29

how is the "crown" of the tooth defined?

Answer 29

clinically- above gingiva | anatomically- covered by enamel

Question 30

what is the root of the tooth?

Answer 30

below the crown, houses pulp cavity and root cavity

Question 31

what is contained in the pulp cavity?

Answer 31

CT, blood vessels and nerves

Question 32

what type of bone is present in dental sockets?

Answer 32

immature/woven bone that can be remodeled (orthodontics)

Question 33

what is the structure of the periodontal ligament?

Answer 33

dense collagenous CT binding the root of the tooth (dentin) to the alveolar bone periosteum

Question 34

describe enamel

Answer 34

acellular, mineralized tissue formed with hydroxyapetite, strongest substance in body, no collagen

Question 35

what produces enamel?

Answer 35

ameloblasts

Question 36

describe cementum

Answer 36

mineral and bone-like avascular covers the root

Question 37

what produces cementum?

Answer 37

cementocytes

Question 38

describe dentin

Answer 38

hydroxyapetite and type I collagen bulk of the tooth located deep to enamel and cementum layers

Question 39

what produces dentin?

Answer 39

odontoblasts

Question 40

describe the components of "mucosa"

Answer 40

- epithelium with basal lamina - lamina propria - muscularis mucosa- smooth mm

Question 41

describe the submucosa

Answer 41

typically dense, irregular CT with blood/lymph, nerves

Question 42

describe the muscularis externa

Answer 42

2 layers - inner circumferential - outer longitudinal

Question 43

describe serosa/adventitia

Answer 43

-mesothelium - simple squamous epithelium | plus CT

Question 44

differentiate serosa and adventitia

Answer 44

called adventitia when the layer of CT is connected to adjacent structures in the body

Question 45

what is the intrinsic innervation of the GI tract?

Answer 45

meissners plexus, Auerbach's plexus

Question 46

what is the extrinsic innervation of the GI tract?

Answer 46

Autonomic (symp, parasymp)

Question 47

where is Meissner's plexus located? function?

Answer 47

submucosa; GI secretion

Question 48

where is Auerbach's plexus located? function?

Answer 48

between the inner and outer layers of the muscular is externa; motor innervation

Question 49

what is the epithelium present in the esophagus?

Answer 49

stratified squamous non-keratinized

Question 50

what is present in the lamina propria of the esophagus?

Answer 50

esophageal cardiac glands, lymph tissue

Question 51

what do esophageal cardiac glands secrete?

Answer 51

neutral mucus

Question 52

what is special about the muscularis mucosa of the esophagus?

Answer 52

has longitudinal orientation only

Question 53

what is present in the submucosa of the esophagus?

Answer 53

dense irregular CT with esophageal glands

Question 54

what do esophageal glands secrete?

Answer 54

lightly acidic mucus for lubrication

Question 55

what is the arrangement of mm in the muscularis externa of the esophagus?

Answer 55

upper 1/3- all skeletal mid 1/3- mix of skeletal and smooth lower 1/3- all smooth

Question 56

what is the innervation of von ebner's glands?

Answer 56

parasympathetic | mediated through CN IX

Question 57

how can the lamina propria be differentiated from the other layers and sublayers?

Answer 57

interdigitates with luminal epithelium, rests on thin smooth mm band (muscularis mucosa)