lecture 6 - gastrointestinal system Flashcards
what is the mechanical process?
muscular movement
what is the chemical process?
hydrolysis by enzymes secreted by the animal, large molecules to smaller molecules until get to the size where they can be absorbed.
what is the microbial process?
enzymic but via enzymes produced by gut micro-organism in colon
what is the overall structure?
mouth to anus, pancreas and liver (gall bladder) - secretes and stores bile
what do the teeth do?
32 permanent teeth, mechanical breakdown
what does the tongue do?
muscular, speech, taste (chemosensory receptors)
what do the salivary glands do?
aids swallowing, secretes salivary amylase and lingual lipase, lubrication and protection
what is the gross structure of the GI tract?
muscular tube
what does the oesophagus do?
links mouth to the stomach, passage of food, no digestion
what is the role of the stomach?
mechanical mixing - chyme, secretes lipase and pepsinogen
what is the hepatic portal vein system?
transports blood from gastrointestinal tract, pancreas, gallbladder and spleen to liver, supplies metabolic substrates and detoxification of ingested toxins
what does the caecum do?
6x9 cm pouch on right side at start of ascending colon; reservoir for chyme
what does the appendix do?
tube-like structure connected to caecum; reservoir for beneficial gut bacteria to repopulate the gut flora and immune function
what does the large intestine do?
microbial digestion of nutrients not digested or absorbed into the SI, minimal lipid digestion
