GI tract histology 2 Flashcards
What is the epithelium type in the oesophagus
Stratified squamous (because this is protective epithelium)
What is the muscular layer like in the different parts of the oesophagus
1st third: Skeletal (voluntary contraction)
Middle: mixed
Last third: Inviluntary
What is the outer layer of the oesophagus like in the thorax and then beyond the diaphragm
Thorax: adventitia
Beyond abdomen: serosa (which allows it to secrete water to reduce friction)
How does the lining change in the gastro-oesophageal junction
Changes from squamous to columnar epithelium
What is Barrats oesophagus
Metaplasia. Change of epithelium from stratified aqua our to columnar (gastric) due to repeated damage from gastric reflux. This is because the stem cells want to protect the oesophagus and columnar epithelium is protective. Adenocarcima may arise (carcinoma of the glands)
Function of stomach
Mixes and churns food breaking it down to fluid chyme and digestion
What is the role of the rugae in the stomach
Folds which increase SA and enable maximal contact between stomach contents and gastric mucosa
What is the epithelium like in the stomach
Columnar epithelial mucous cells to protect stomach lining from acid
What are gastric pits and glands
gastric pits and glands contain the epithelial cell types which break down food
Function of the inner oblique muscle layer of the stomach
Churn the contents of stomach in different ways
What is peristalsis
Wave like muscle contractions that move food in digestive system
Cells found in gastric pits and glands
Mucous cells
Parietal cells
Chief cells
Enteroendocrine cells
What do mucous cells produce
Mucus and bicarbonate which protects surface from acid and digestion
