HIST of the GIT - Week 5 Flashcards
Epithelium of esophageal mucosa layer.
Stratified squamous cells.
Epithelium of stomach.
Simple columnar cells w gastric pits & glands.
Are goblet cells found in the stomach?
No.
What 3 x structures in the SI increase SA:V ratio?
Villi, microvilli, plicae circulares.
What is found within the Crypts of Lieberkuhn?
Stem cells which create the epithelial layer.
Where are Brunner’s glands located? What is their function?
Duodenum. Secrete alkaline mucous into Crypts, then into the lumen to protect the epithelium.
Compare & contrast histology of duodenum and ileum.
In the ileum, villi are shorter. Distal region characterised by lymphoid follicles/Peyer’s patches w high concentration of lymphocytes.
Main function of the colon.
Secrete mucous to assist with the transport of faeces and to absorb electrolytes & water. NB: High goblet cells present, but no villi. Crypts present.
What is the portal triad composed of?
Portal triad = portal vein + common bile duct + hepatic artery proper.
Islet of Langehan function.
Endocrine cells which secrete hormones directly into the bloodstream.
Function of the plicae circularis.
Forms a cylinder like orientated which forces food to pass through the bowel in a circular, looped motion to increase the amount of time food spends in the digestive tract rather than letting it pass straight through like a slide.
Blood vessels in hepatocytes structure and blood flow.
Blood vessels in hepatocytes are fenestrated, endothelial blood cells. These blood cells are very leaky. Plasma from these blood vessels flows from these cells via sinusoids -> central vein -> IVC. NB: RBCs cannot pass though fenestrated pores in endothelial blood cells.
Exocrine acini cells function.
Secrete digestive enzymes into the stomach & digestive tract via ducts.
Epithelium of the gall bladder.
Simple columnar.
