Histology Labs 15 & 16 - Digestive Tract

Antigen transporting cells

M cells

Blind-end lymphatic capillaries which function as the entry site for most absorbed lipids

Lacteals

'Bulges' on the external surface of the colon

Haustrae

Cell type activated by the hormone gastrin

Parietal cells

Cell type displaying a digestive-enzyme-containing glycocalyx

Enterocyte

Cell type displaying an intracellular canalicular system

Parietal cells

Cell type displaying intraepithelial pockets, where lymphocytes and antigen-presenting cells reside

M cells

Cell type lining the lumen and gastric pits of the stomach

Surface mucous cell

Cell type lining the lumen of the small and large intestine

Enterocyte

Cell type overlying regions of lamina propria containing abundant lymphatic tissue

M cells

Cell type which produces the 'mucous blanket' necessary to protect the stomach lining from acidic chyme

Surface mucous cell

Cell type which secretes a thick, viscous, gel-like mucus and bicarbonate

Surface mucous cell

Cell type which secretes antimicrobial substances such as lysozyme

Paneth cell

Cell type which secretes HCl and intrinsic factor

Parietal cell

Cell type which transports IgA from the lamina propria to the lumen of the intestine

Enterocyte

Cell type with membrane lined by H+/K+-ATPase proton pumps

Parietal cell

Dense, irregular fibroelastic connective tissue layer of digestive tract organs

Submucosa

Found along the length of esophagus; provide secretions to lubricate lumenal surface

Esophageal mucosal glands

Functions to decrease velocity of chyme and increase surface area for absorption

Plicae circularies

Function(s) carried out by muscularis externa

Peristalsis and segmental contractions

Glands similar in functions to the esophageal cardiac glands

Stomach cardiac glands

Glands where parietal and chief cells are located

Gastric glands

Glands which secrete alkaline mucous and bicarbonate to neutralize the acidic chyme

Brunner's glands

Glycocalyx-located enzyme which cleaves trypsinogen

Enteropeptidase

Hormone which acts on pyloric sphincter and slows emptying of stomach

CCK

Hormone which inhibits gastrin release

Somatostatin

Hormone which stimulates the release of bile from the gallbladder

CCK

Hormone which stimulates secretion of pancreatic enzymes

CCK

Hormone which stimulates pancreatic bicarbonate secretion

Secretin

Hormone-secreting cells located in gastric glands and crypts of Liekerkühn

Enteroendocrine

Innate immunity cell type found at the base of the crypts of Lieberkühn

Paneth cells

Layer of the digestive tract containing 2-3 layers of smooth muscle

Muscularis externa

Layer which protects the gastric lining from physical abrasion and acidic chyme

Mucous blanket

Location of Brunner's glands

Submucosa of duodenum

Longitudinal folds of the stomach

Rugae

Loose connective tissue layer underlying the epithelia of digestive tract organs

Lamina propria

Major function of this organ is the recovery of sodium and water

Colon

Molecules which bind to taste receptors

Tastants

Organ which displays villi

Small intestine

Organ with displays taeniae coli

Colon

Organ(s) displaying mucous glands called crypts of Lieberkühn

Small and large intestine

Organ of the digestive tract displaying skeletal muscle

Esophagus

Organ of the digestive tract displaying stratified squamous epithelia

Esophagus

Organ(s) of the digestive tract displaying submucosal glands

Esophagus, duodenum

Outer most layer(s) of digestive tract organs

Serosa or adventitia

Permanent transverse folds of the colon

Plicae circulares

Similar to colon but with increased lymphatic tissue, shorter crypts and no taeniae coli

Appendix

Smooth muscle layer of the mucosa

Muscularis mucosa

Stomach glands which provide secretions to protect esophageal mucosa from regurgitated gastric contents

Cardiac

Structure which results in a 600 fold surface area amplification in the small intestine

Microvilli

Term referring to the ducts of stomach mucosal glands

Gastric pits

Three narrow, thickened, equally-spaced longitudinal ribbons of smooth muscle found in the colon

Teniae coli

Tissue type lining the lumens of the digestive tract organs

Epithelia

Type of lingual papillae lacking taste buds

Filiform

Type of lingual papillae with taste buds on apical surface

Foliate, Circumvallate

Type(s) of lingual papillae with taste buds on lateral surfaces

Fungiform

Unicellular exocrine glands which secrete heavily glycosylated proteins called mucins

Goblet cells