Lab 11 Flashcards
chemical digestion in mouth:
salivary amilase and lingual lipase
3 salivary glands:
parotid, submandibular, sublingual glands
histological features of salivary glands:
- Collection of secretory cells, adipose tissue
and ducts - Variable staining secretory cells arranged as acini
(clusters)
o Mucus acini
o Serous acini - Ducts lined by simple cuboidal epithelium
three regions of the pharynx:
what type of muscle is pharynx?
naso-, oro-, and laryngo- (oropharynx receives bolus) and sends to esophogus
skeletal (voluntary swallowing)
what type of muscle is esophagus?
smooth (involuntary peristalsis)
esophagus runs within the mediastinum and enters the
abdominopelvic cavity through the _____
esophageal hiatus
where does the esophagus join the stomach?
at the cardiac
sphincter (valve)
Four basic layers (tunics) of the GI tract:
- Mucosa
- Submucosa
- Muscularis Externa
- Serosa/Adventitia
histology of the esophagus
- Star-shaped lumen
- Mucosa─ contains stratified
squamous epithelium - Submucosa─ composed of
areolar connective tissue;
contains mucus glands - Muscularis externa─
composed of circular and
longitudinal smooth muscle - Adventitia─ composed of
connective tissue
what kind of digestion happens in the stomach
-enzymatic digestion of proteins by pepsin
-minimal site of absorption (alcohol, meds)
-b12 w intrinsic factor
-HCl
-turns bolus into chyme
-3 smooth muscle layers for peristalsis and churning (oblique, circular and longitudinal)
name the specialized cells in the gastric pits of the stomach mucosa:
parietal cells, chief cells, mucous neck cells, and enteroendocrine cells
parietal cells secrete
HCl and intrinsic
factor
chief cells secrete
Inactive enzyme pepsinogen
mucous neck cells secrete
thin mucous
enteroendocrine cells secrete
Serotonin, histamine,
somatostatin and
gastrin
how does epithelia change at the cardiac sphincter?
changes from stratified squamous in esophagus to simple columnar in stomach
histological features of the stomach
simple columnar epithelium at lumen, gastric pits, and gastric glands
histological features of the SI
circular folds and villi, and intestinal crypts in the mucosal layer, and lumen lined by simple columnar epithelia with goblet cells (produce mucus)
histological features of the duodenum
presence of light-staining brunner’s glands (submucosal duodenal glands) that produce alkaline mucus
histological feature of the ileum
dark staining peyer’s patches: lymphatic tissue that protects from pathogens near the ileocecal valve
site of appendix:
cecum
colon parts
ascending (right side), transverse, descending (left side), sigmoid colon (then into rectum)
histological features of the large intestine (colon)
crypts of lieberkuhn; circular and longitudinal muscle layer
