Digestive System - Part II Flashcards
glands of ____ located in submucosa of duodenum
Brunner (tubuloacinar glands)
glands of duodenum empty contents into ______, then those contents find their way to the lumen
crypts of Lieberkuhn
submucosal intestinal glands of Brunner secrete contents in response to _____, _____, _____
direct tactile stimulus or irritation, vagal stimulation, intestinal hormones
functions of Brunner’s glands secretions?
protect duodenum wall from digestion
_____ help maintain a barrier between the environment and the internal milieu of the body
Peyer’s patches
_____ are groups of unusual or odd cells that cover Peyer’s patches
M-cells
_____ are antigen presenting cells
M-cells
define transcytosis
type of transcellular transport in which various macromolecules are transported across the interior of the cell
____ are transferred from lamina propria to lumen by transcytosis
antibodies
large intestine: ____ are longitudinal muscle in three flat bands in humans
taeniae coli
_____ are sac like bulges in the large intestine
haustrations
numerous ____ in the large intestine crypts of Lieberkuhn
goblet cells
difference between the luminal surfaces of the large and small intestine?
no villi in large intestine
large intestine also has a very thick mucosa layer
how do crypts of lieberkuhn differ throughout the intestine?
- in the small intestine: contents are zymogenic cells - paneth cells and argentaffin cells
- in the large intestine and appendix: mostly made up of goblet cells
how does the villi change throughout the small intestine?
- duodenum: medium
- jejunum: tall and slender
- ileum: low and broad
cells located in the epithelium of the intestine:
____, ____, _____, ____
absorptive cells, goblet cells, argentaffin cells, paneth cells (and cells of duodenal glands - Brunner’s glands)
characteristics of an intestinal absorptive cell?
brush border, glycocalyx, terminal web, elongated mitochondria, large Golgi complex, SER and RER, interdigitation of lateral surfaces
two roles of the brush border glycocalyx?
protection against enzymes
active in digestion
_____ are discharged at the basal membrane into the lacteal.
chylomicrons
Where are paneth cells located?
at the depths of the crypts of Lieberkuhn
_____ are unicellular glands, flattened nucleus, short-lived
goblet cells
function of mucus in large intestine?
protects wall against excoriation, provides adherent qualities to feces, and protects wall against bacterial activity
three key steps in combating infections?
Break the cycle of transmission
Kill the infectious agent
Increase the host resistance
first line of defense immunologically in the intestines
mucus
