Digestive System Flashcards
functions of digestive system
- ingestion
- secretion
- propulsion
- digestion
- absorption
- defecation
definition of digestion
the mechanical and chemical breakdown of large ingested food particles into smaller molecules that may be easily absorbed by body cells
alimentary canal
continuous tube extending from mouth to anus
gross anatomic pathway
includes hollow organs in direct contact with food
accessory organs of digestive system
salivary glands, liver, gallbladder, pancreas
layers of alimentary canal wall
- deep to superficial*
- mucosa
- submucosa
- muscularis
- serosa/adventitia
purpose of submucosa
- binds mucosa to muscularis
- reabsorbs food molecules from the mucosa
serosa/adventita
- outermost connective tissue layer
- decrease friction associated with gut motility
segmentations
- mixing contractions
- mix chyme digestive fluids
- food particles with mucosa brush border enzymes
propelling movements
-peristaltic movements
modified peristaltic movements
ENS (enteric nervous system)
- brain of the gut
- can function independently
- subject to regulation by ANS
parasympathetic innervation
increase in GI secretion/motility
sympathetic innervation
decrease in GI secretion/motility
peritoneum
- parietal (lines wall)
- visceral (lines organs) acts as serosa
purpose peritoneal cavity
allows friction free movement of viscera
