intro Flashcards
function of stomach
Digestion of proteins; foodstuffs
function of liver
Bile salts for digestion/absorption of fats in small intestine
function of pancreas
Digestive enzymes for digestion of fats, carbohydrates and proteins
function of gallbladder
: Stores and concentrates bile
small intestine function
Final stages of chemical digestion and nutrient absorption
large intestine function
Water absorption, bacterial fermentation and formation of faeces
what are the layers of the alimentary canal
mucosa - epithelium, lamina propria, muscularis mucosae
submucosa
muscularis externa
adventitia/serosa
what parts have stratified squamous epithelium
Mouth, oesophagus, anal canal
what parts have simple columnar
Stomach, small & large intestine
what plexus is in the submucosa
submucosal plexus (meissners) - parasympathetic
where do you get serosa
Inside peritoneal cavity
where do you get adventitia
Outside peritoneal cavity
describe muscularis externa
2 layers
Inner layer = circular muscle (constricts lumen)
Outer layer = longitudinal muscle (shortens tube)
myenteeric plexus, between layers
function of muscularis externa
Produce motility -> peristalsis, segmentation
what forms the enteric plexus
Submucosal + myenteric plexuses = enteric nervous system (ENS) -> independent control of gut function
autonomic control of alimentary function
Long (parasympathetic) and short (ENS) reflexes
parasymp control of alimentary function
vagus nerve (X) except salivation -> VII and IX
inc secretion
inc motility
symp control of alimentary function
splanchnic nerve
dec secretion
dec motility
main arteries that supply GI system
from descending aorta
- celiac
- superior mesenteric A
- inferior mesenteric A
what does celiac trunk supply
Stomach
Small intestine
Pancreas
Liver
what does superior mesenteric A supply
Small intestine
Caecum
Ascending colon
Transverse colon
what does inferior mesenteric A supply
Descending colon
Sigmoid colon
Rectum
venous drainage of stomach
gastric vein -> hepatic portal vein -> hepatic vein -> IVC
venous drainage of pancreas
splenic vein -> hepatic portal vein -> hepatic vein -> IVC
