Grand Tour of the Alimentary Canal Flashcards
what nerves stimulate salivation?
facial VII and glossopharyngeal IX
what effect does excitation of the vagus nerve have on gut motility and secretion?
increases both
what is the sympathetic innervation of the gut?
splanchnic nerve
what effect does excitation of the splanchnic nerve have on gut motility and secretion?
decreases both
what nerve’s action will increase salivation?
splanchnic nerve (sympathetic)
what arterial branch supplies the stomach?
coeliac trunk
what arterial branch supplies the ascending colon?
superior mesenteric artery
what arterial branch supplies the descending colon?
inferior mesenteric artery
what are the 3 branches of the abdominal aorta?
coeliac trunk, SMA and IMA
what are the 3 main branches off the coeliac trunk?
common hepatic artery, left gastric artery and splenic artery
from inside to outside what are the 4 layers of the alimentary canal?
mucosa, submucosa, muscularis externa and serosa/adventitia
what 3 layers comprise the mucosa?
epithelium, lamina propriae and muscularis mucosa
what type of epithelium exists in the mouth oesophagus and anal canal?
stratified squamous
what type of epithelium exists in the stomach, small intestine and large intestine?
simple columnar
what are the 3 main functions of gut epithelium?
- barrier to seperate inside and out
- make and secrete mucus, hormones and enzymes
- absorb products of digestion
what is the lamina propriae?
loose connective tissue with glands, blood vessels and lymph vessels
what two directions of muscle exist in the muscularis externa?
longitudinal and circumferential
where is the submucosal plexus?
within the submucosa
where is the myenteric (Auerbach’s) plexus
within the muscularis externa, between the circular and longitudinal muscle layers
what two plexuses make up the enteric nervous system?
submucosal and myenteric plexuses
which is most outermost muscle layer of muscularis externa?
longitudinal
what organ does all gut blood pass through on its way to the heart?
liver
where does the liver get its arterial supply from?
the hepatic artery
why does all the gut blood need to pass through the liver before it can go back to the heart
to extract nutrients and toxins from digestion now circulating in blood
