Histology Flashcards
what type of epithelium lines the oral cavity
stratified squamous non-cornified epithelium
what type of epithelium covers regions encountering abrasive/shearing forces
(especially lips, gingiva and hard palate)
stratified squamous parakeritinized
what type of secretions does the parotid gland do
serous
what type of secretions does the submandibular gland produce?
mixed (serous and mucous)
what type of secretions does the sublingual gland produce?
mucous
WHAT type of epithelium is on the external aspect of lips?
stratified squamous cornified
what type of epithelium is in the internal asepct of lip
stratified sqaumous non-cornified
wet!!
are there hair follicles or sweat glands in the vermillion zone?
no
what type of epithelium are the gums?
what type of CT and what type of Collagen
stratified squamous epithelium (either partially or fully cornified)
dense, irregular connective tissue
principal fiber groups formed by type I collagen fibers
what are the glands of nuhn
mucous glands on tongue
what are the glands of ebner
serous glands on tongue
which lingual papilla does NOT have taste buds
filiform papillae
which papillae resembles a mushroom and contains taste buds on dorsal surface
fungiform paillae
which papillae of the tongue is located along the posterolateral aspect of tongue and has taste buds that degenerate as a child
foliate papillae
which papillae are surrouded by valleys and are associated with von ebner glands and contain taste buds on the lateral surface
circumvallate papillae
what are the three cell types in the taste bud
gustatory (neuroepithelial cells)
sustenacular cells
basal cells
what are the 5 taste sensations
salty sour sweet bitter savory (umami)
what taste sensations are mediated by specific ion channels
salty
sour
what taste sensations are mediated by membrane receptors
sweet
bitter
savory
complex taste perception is largely a function of what sensory element?
olfaction
what are the 4 main layers from lumen outward in the gut
mucosa
submucosa
muscularis externa
adventitia
what are the 3 layers of the mucosa
epithelium
lamina propria
muscularis mucosae
what are the 2 (sometimes 3) layers of the muscularis mucosae of the mucosa layer
inner circular layer outer longitudinal layer 3rd layer (stomach) --> luminal/longitudinal oblique layer
from what embryological layer does the epithelial lining of GI tract arise
endoderm
from what embryological layer does the CT and smooth muscle of GI tract arise
mesoderm
what parts of the small intestine are peritonealized and which are retroperitonealized
peritonealized –> jéjunum and ileum
retroperitonealized –> duodenum
which parts of the large intestine are retroperitonealized and which are peritonealized
retroperitoneal:
- ascending
- descending
peritonealized:
- transverse
- sigmoid
what does the pectinate line in the anal canal demarcate ?
from simple columnar to stratified squamous (wet)
what is the cardioesophageal junction
transition from esophagus to stomach sudden change from stratified squamous to simple columnar epithelium
are there goblet cells in the stomach?
NO
does the large intestine have villi?
no
what is the shape of villus in the duodenum, jejunum and ileum
in duodenum - broad, short and leaf-like in jejunum - tongue-like projections in ileum - tall, narrow, finger-like projections
what makes up the core of a villus
lamina propria
what makes up the core of a plicae circularis
submucosa
what are brunner’s glands
mucous secreting cells in the submucosa of duodenum only
as we move down the GI tract what happens to the number of goblet cells
increases
what type of epithelium lines the small intestine
simple columnar
what are some of the products of enterendocrine cells of the small intestine
found mainly in crypts, occasionally (rarely) in villus
secrete product into vascular channels in lamina propria
products include: incretins (K-cells) GIP (L-cells) serotonin (enterochromaffin cells) somatostatin- stasis motilin cholecystokinin neurotensin VIP substance P endorphins
where are paneth cells found
intestinal crypts
where are M cells found
epithelium on small intestine
what is the function of paneth cells
secrete enzyme lysozyme & peptide defensins
degrade components of bacterial cell wall
The secretion of these cells go into the lumen
what is the function of M cells
part of innate and classic immune systems
actively capture/transport Ag’s to APCs & B cells in lamina propria
what part of the duodenum has serosa and what part has adventitia
the anterior part has a serosa
the posterior part has adventitia (retroperitoneal)
where are peyer’s patches found
ileum, jejunum, large intestine
do the ileum and jejunum have serosa?
yes
are there villi in the large intestine?
no
are paneth cells in the large intestine
no
what are crypts of Lieberkuhn
these are the intestinal crypts in the large intestine (longer and more closely packed)
instead of plicae circularis like the small intestine, what is present in the large intestine
plica semilunaris
produce haustra
where does tenia coli become continous again
rectum
where are plica transversali found
rectum
what occurs at the pectinate line
simple columnar to stratified squamous non-cornified
what occurs in the epithelium at the caudal portion of the anal canal
epithelium changes to stratified squamous keratinzed
from what tissue layer does the pancreas form
endoderm
what do the alpha cells of pancreas produce
glucagon
what do the beta cells produce (pancreas)
insulin
amylin
what do delta cells of pancreas produce
somatostatin
what doe the PP cells pancreas produce
pancreatic polypeptide
what do the delta-1 (minor ) produce
VIP
what do EC beta cells produce
secretin
motilin
substance P
what doe epsilon cells produce
ghrelin
what are stimulatory inputs to the pancreas
glucose, amino acids, glucagon, GIP, CCK, sulfonylurea compounds, b-sympathetic fibers
what are inhibitory inputs to the pancreas
somatostatin, amylin, pancreastatin, α-sympathetic fibers
what is the function of pancreatic polypeptide
stimulates gastric chief cells
inhibits bile secretion and intestinal motility
inhibits pancreatic enzymes and HCO3 secretion (bicarb)
what is the function of VIP
Similar to action of glucagon (hyperglycemic and glycogenolytic)
Also affects secretory activity and motility in gut
Stimulates pancreatic exocrine secretion
what is the function of secretin
acts locally:
stimulates HCO3 secretion (in pancreatic juice)
stimulates pancreatic enzyme secretion
what is the function of motilin
increases gastric and intestinal motility
what is the function of ghrelin
appetite stimulant
which cells are the first cell that blood usually encounters in the islet
beta cells