Feb13 M1-Histo 1 Flashcards
4 histo layers in GI tract
- mucosa
- submucosa
- tunica muscularis
- adventitia (esophagus) or serosa (visceral peritoneum)
3 layers of mucosa
- nonker squamous stratified epith
- BM
- lamina propria
- muscularis mucosa
cells shapes in squamous stratif epith
bottom: columnar
middle: polygonal
top: squamous
LP contents (in esophagus)
loose CT (lot of cells), mucous glands in upper and lower third of esophagus called cardiac esophageal glands
muscularis mucosa def
SM cells running along GI tube axis.
submucosa contents in esophagus
loose and dense CT mixture + esophageal glands proper: mucous glands giving mucous coat to esophagus for lubricatio. gland opens with duct at lumen
tunica muscularis 2 layers in esophagus
- inner circular running along circumference
- external longitudinal running along GI tube axis
adventitia in esophagus def + fct
dense irregular CT. connects esophagus to other organs of the mediastinum
2 nerve plexuses and location in the GI tube
Meissner’s plexus: in submucosa
Auerbach’s plexus: between inner circular and external longitudinal
Meissner’s plexus fct
(submucosa) PSS innervation to secretory glands
Auerbach’s plexus fct
(between inner circular and outer long) SS and PSS fibers to SM cells
Auerbach’s plexus contents
ganglion cells and unmyelinated nerves
Meissner’s plexus contents
ganglion cells and nerves
missing histo layer in upper esophagus
muscularis mucosa of the mucosa (present only below upper esophagus)
glands along the esophagus
upper: cardiac esophageal glands (LP)
middle: esophageal glands proper (submucosa) (prof says mixed with cardiac esophageal glands)
lower: cardiac esophageal glands (LP)
tunica muscularis content in esophagus
upper: skeletal muscle continuous with pharynx
middle: combination of SKM and SM
lower: SM (inner circular and outer longit)
name of the line between stomach and esophagus and clinical importance
gastroesophageal junction or Z-line
GERD: heartburn
what forms the LES (internal and external)
internal: thickening of the inner circular of the tunica muscularis (esophagus)
external: diaphragm
3 fcts of stomach
- HCl (ph 2)
- IF for B12 abso
- gastrin and sts
characteristic of gastric mucosa
rugae (folds of the mucosa)
2 portions of the gastric mucosa
folds (rugae) and pits (slits between the rugae. are opening of glands)
cells and epith charact in the gastric mucosa
SIMPLE columnar epithelium: surface mucous cells (rugae and pits. pits = openings of glands) and secretory mucous cells (for glands extending within the LP)
charact of the muscularis mucosa in the stomach
instead of 1 longitudinal layer, has inner circular and outer longitudinal
charact of submucosa in stomach
Meissner’s plexus (PSS for glands)