Lecture 1 Flashcards
Layers of the gut
- Mucosa
- Submucosa
- Muscularis Externa
- Adventitia/Serosa
3 layers of mucosa
- Epithelium (secretion, absorbtion and protection)
- Lamina propria (blood vessels and lymphatic)
- Muscularis Mucosae (independent movement of musocsa)
Submucosa nerve plexus name
Meissners nerve plexus
- secretion rates and blood flow
- motility
Muscularis externa functions
Peristaltic movement of the gut via smooth muscle (circular and longitudinal)
Serosa location
If suspended by a mesentry and covered by the peritoneum
Adventitia
If retroperitoneal with no mesentry
Components of the alimentary tract
Oesophagus
Stomach
Small intestine (duodeenum, jejunum, ileum)
Large intestine
Function of oesophagus
Type of epoithelium
Muscle spread
Transport masticated material from pharynx to stomach
stratified squamous non keratinising epithelium
Upper third, voluntary skeletal muscle
Middle- mix
Lower- involuntary smooth muscle
Stomach
Components
Rugae- temoyry folds in mucosa Mucosa - simple columnar Muscularis mucosa Submucosa Muscularis Externa - 3 layers, circular, longitudinal and oblique
Gastric pits and glands
Components and signifigance
Upper portion pits and lower glands
Mucous cell- lubrication
Parietal cell- produces HCL
Enteroendocrine cell- produces gastrin for secretion and blood rates
Chief cell- granules contain pepsiogen for protein breakdown
Small intestine
3 components
Explaination of - crypts, enterocytes, enteroendocrine cells
Plicae circulares
- circular ridges projecting in
Villi
- projecting from the plicae circulares
- crypts of lieberkhun- cell factories