9/24 Histology of digestive system Flashcards
what is the general type of epithelium in the oral cavity?
stratified squamous: both deratinized (ortho and para) and non-keratininzed
what is the embriological origin of the oral cavity
derived from ectoderm, like skin, not endoderm like the rest of the gut
what is the average turn over of the stratified squamous of the oral cavity
1-2 weeks
the underlying connective tissue
lamina propria
How and why is there a large immune pressence in the oral cavity
many lymphocytes and the tonsils, 3X10^9 PMNs enter lamina propria everyday, and small mixeed sero/mucous salivary glands. all to take care of small immune responses to the large number of pathogens in the mouth
what covers the back of the toungue
lymphatic tissue, and the palatine tonsil
the structure near the back of the tounge wear most taste happens
circumvallate papilla
the structures on the majority of the dorsal surface of the toungue that taste
fungiform papilla
the structures of the dorsal of the tounge that cover most of the surface
filiform papilla
The layers of the tounge in the microscope
stratisfied epithelium; loose or dense connective tissue (lamina prpria) then striated skeletal muscle and adipose tissue
why do you have skeletal muscle tissue in the tounge
moves food back, and requeired for normal speech. arranged in all kinds of orientations
The most common form of cell on the dorsal surface of the tounge
filiform papillae
the moat that surrounds the circumvallate papillae
crypt
why does the circumvallate papillae have crypt
has glandular structures to wash material out to allow constant tasting of new things
the glands that wash out the crypt
Von Ebner’s gland: serous glands, they appear as globular structure in the connective tissue with ducts associated with the crypt
what is the purpose of saliva
lubricate the mouth w/mucous secretion. amylase in serous secretion (digest carbs). Helps prevent infection!
purpose of the salivary glands
Make saliva; get infected (mumps, and impacted ducts); growth factors; make haptocorrin.
how does salive act as defensive agent?
secrete lactoferrin (iron binding protien against bacteria), lysozyme (desolve bacteria cell walls), and defensins (anti-biotic protiens) and transport IgA (binds to pathogens)
what is haptocorrin?
a vitamin B12 binding protein
why would the saliva produce growth factors?
maybe to promote wound healing in the mouth and in other parts of the body when you lick wounds
cells that secrete in a serous fashion and are a spherical gland
Serous acinus
Glands that produce mucous
mucous tubule
combinded serous and mucous cells in a singe duct
mucous tubule and serous demilune
the course of mucous and serous once produced form serous acinus/demilune and mucous tubule
glands connected to intercalated ducts, striated ducts, and interlobular ducts