GI Histo I Flashcards
tongue: skeletal muscle is covered with what kind of membrane
mucous
elevations of oral epithelium on the dorsal surface called
papilla
taste buds are found on ____ of the papilla
some
papillae types: no taste buds, conical in appearance; increase friction between tongue and food and is keratinized. FOUND ALL OVER TONGUE
filiform papillae (dorsal fins of a shark)
papillae types: have some taste buds; FOUND AT MARGINS OF TONGUE
fungiform papillae (surrounding it are filiform papillae)
papillae types: found on the posterior aspect of the tongue, have Ebner’s glands and many taste buds
(circum) vallate papillae (mushrooms that have tilted over)
papillae types: poorly developed in humans and have many taste buds
foliate papillae
structures containing taste cells; onion shaped with microvilli, rest in the basal lamina
taste bud
how many teeth in adult mouth
32 permanent
teeth are divided into 2 parts
- crown - above gum
2. root - below gingiva; keeps tooth in alveolar socket
what are the 5 components of teeth
- enamel
- cementum
- dentin
- pulp
- periodontium
surrounds the crown and is produced by AMELOBLAST cells (hardest substance in the body)
enamel
surrounds the root and is produced by CEMENTOBLASTS
cementum
deeper than both enamel and cementum and is produced by ODONTOBLASTS
dentin
highly vascularized and innervated. PAIN SENSITIVE (lowest part is where root canal is performed)
pulp
part that keeps tooth in the socket
periodontium
- alveoli bone
- periodontal ligament
- cementum
- gingiva
alimentary canal: 4 layers
- mucosa
- submucosa
- muscularis externa
- serosa/adventitia
alimentary canal: blood vessels, lymphoid tissue and meissner’s plexus
submucosa
alimentary canal: smooth muscle layers which function in peristalsis (inner- circular, outer - longitudinal) and auerbach’s (myenteric plexus)
muscularis externa
controls motility of the mucosal layer and secretions from the glands (post gang p/s)
Meissner’s plexus
controls motility of the smooth muscle wall and also has post gang p/s
auerbach’s myenteric plexus
alimentary canal: outermost layer - with connective tissue only called ____
serosa/adventitia
adventitia
what are the 4 walls of the esophagus
- mucosa
- submucosa
- muscularis externa
- adventitia/serosa
esophagus: stratified squamous epithelium (non-keratin)
mucosa
esophagus: has submucosal glands called esophageal glands proper
submucosa
esophagus: upper 1/3 vs lower 1/3
muscularis externa
upper : skeletal
lower : smooth
what are the 4 anatomic regions of the stomach
- cardia
- fundus
- body
- pylorus
the ___ and ___ are identical histologically in the stomach
body and fundus
what are the 3 different glands observed in the stomach
- cardiac
- gastric (fundic/body)
- pyloric
the muscularis externa of the stomach has 3 layers
- internal oblique
- middle circular
- outer longitudinal smooth
gastric gland: shallow crypts with coiled bases
cardiac glands
gastric gland: long and tubular with 3 distinct regions: isthmus, neck and base
gastric (fundic) glands
gastric gland - fundic gland region: parietal cells, chief cells and enteroendocrine cells which secrete serotonin here
base
what are the 5 different cells of the fundus
- undifferentiated cells
- mucous neck cells
- parietal cells
- chief cells
- enteroendocrine cells
fundus: neck of gland, oval basal nuclei, distinct nucleolus, mitotic, stem cells, surface cells survive 3-7 days
undifferentiated cells
fundus: basal irregular nuclei, mucous granules
mucous neck cells
fundus: found in the upper half of glands, many mitochondria, eosinophilic staining
parietal cells
- produce HCL
fundus: mostly at base of glands, basophilic ribosomes
chief cells
- produces pepsinogen and lipase
fundus: secrete serotonin and found at the base of glands
enteroendocrine cells
what 3 cells are seen in the pyloric glands
- mucous cells
- gastrin cells
- D cells
pyloric: secrete lysozyme - pale staining and most plentiful
mucous cells
pyloric: found at the base of the base of the which secretes gastrin
gastrin cells
- gastrin leads to increase HCL output
pyloric: secrete somatostatin which inhibits gastrin secretion
D cells
the crypts of the small intestine have what 6 cells
- stem cells
- absorptive cells
- goblet cells
- paneth cells
- membranous epithelial cells (peyer’s patches)
- endocrine hormone cells
small intestine: in the submucosa of the duodenum that secrete alkaline substance to help neutralize the acidic pH from the stomach
brunner’s glands (duodenal glands)
small intestine: mucosa and submucosa fold into
plicae circularis or valves (folds) of Kerckring
small intestine: lymphatic channel that absorbs dietary fats in the villi
lacteal
which cell of the SI will you see with micovilli
absorptive cells
- apical surface in brush border
which cell of the SI is
- few in duodenum, many in ileum
- produce acid mucous to protect and lubricate epithelum
goblet cells
which cell of the SI is on the basal area of the gland and is an exocrine serous cell
paneth cells
function of SI cells: basophilic cytoplasm, eosinophilic granules containing _____
lysozyme
cells of the SI that have hormones such as: gastrin, secretin, cholecystokinin, somatostatin, motilin, etc.
enteroendocrine cell (APUD cell or DNES cell)
