GI histology Flashcards
what are the layers of gut tube?
Mucosa
Epithelium
Lamina Propria
Muscularis mucosae
Submucosa
Muscularis externa
Inner circular
Outer longitudinal
Adventitia /Serosa
what are characteristics of the layers in the oesophagus?
Stratified squamous non-keratinised epithelium
Submucosa shows mucous glands
Muscular layer – upper 1/3 skeletal, middle 1/3 – smooth+ skeletal, lower 1/3 - smooth
what do parietal cells secrete?
HCL
what do chief cells secrete?
pepsinogen
what are characteristics of the layers in the small intestines
Villi
Crypts of Leiberkuhn
Lymphoid aggregations in mucosa - Peyer’s patches
what are characteristics of the layers in ileum?
Villi +
Peyer’s patches
what are characteristics of the layers in the large intestine?
Thick mucosa, crypts, mucous secreting cells. No villi.
what are the glands in the GI?
Salivary glands (in head/neck block)
Pancreas
Liver (very elaborate gland!)
what are Secretory (acinar component) – roundish structure with columnar cells and nuclei at the base
Ducts
characteristics of the pancreas?
Islet of Langerhans – endocrine part – no acini
2 – exocrine part – pancreatic acini
3 – pancreatic duct ( for exocrine part)
what are the regions of the stomach?
cardia
fundus
body
pylorus
functions of the stomach
Food starts to be digested and absorbed in the stomach.
Food is broken down chemically, by gastric juice, and mechanically, by contraction of the three layers of smooth muscle in the muscular externa layer. The broken up food at the end of this process is called chyme.
what are rugae?
folds found on the interior layer of the stomach and aid in breaking down food when the stomach contracts.
what are gastric pits?
are indentations in the stomach epithelium which denote entrances to the tubular shaped gastric glands. The human stomach has several million of these pits which dot the surface of the lining epithelium
what are the three types of gland?
cardiac – secrete mucus;
fundic – secrete HCl and intrinsic factor;
pyloric – secrete gastrin