What does physical and chemical digestion do to the food?
reduces food size and solubility to be better absorbed
Define absorption
the entrance of “food” molecules across the gut lining
What substances can be absorbed?
amino acids, sugars and carbs, glycerol & fatty acids, some minerals and water
How does chemical and physical digestion differ?
chemical digestion uses enzymes, physical uses mechanical manipulation in order to increases SA for enzymes to work on
What does salivary amylase do?
starch to maltose
pharynx vs larynx?
pharynx: back of the throat, common passageway, where food is swallowed larynx: hollow tube in the middle of the throat, can help breathe
What is chyme?
mushy liquid created by physical digestion in the stomach for more surface area
Where does the chemical digestion of proteins begin?
stomach
Explain the domino of gastric excretions.
Gastrin, a hormone hits the blood and stimulates production of pepsinogen (pepsin), pepsin chemically digests protein into peptides
What happens in the duodenum?
All 3 food groups are chemically digested here. Enzymes from pancreas and small intestine digest. Bile from the liver and stored in the gall bladder also released and helps emulsify fat
what enzymes does the pancreas produce and what do they break down into which product?
- pancreatic amylase: starch > maltose 2. trypsin: protein > peptides 3. lipase: fat droplets > glycerol and fatty acids 4. nuclease : nucleic acid (DNA/RNA) > nucleotides
What enzyme does the small intestine produce and what do they break down into which product?
1.peptidases: peptides > amino acids 2.maltase: maltose > glucose 3.nucleosidases > base, sugar,phosphate
What hormones does the duodenum produce and what is its purpose?
- Secretin: acidic chyme, esp HCl, triggers its secretion, stimulates release of pancreatic juices 2. CCK (chlorocytokenin): triggered by acid chyme, stimulates release of bile from gall bladder
What protects duodenum from acid chyme?
sodium bicarbonate entering the duodenum
What makes the small intestine specialized for digestion?
- folded walls for ^ SA 2. walls of the intestine have villi which have microvilli along their lining , + blood vessels and lacteal inside each villi
the formula for mastase from the small intestine?
1 mastose + water = 2 glucose
the formula for pepsin/trysin from the stomach/pancreas?
protein + water = peptides
the formula for peptidases from the small intestine?
peptides + water = amino acids
the formula for bile produced by the liver, stored in the gall bladder and released into the duodenum to emulsify fats by chyme triggering CCK
fat > fat droplets
formula for lipase from the
fat droplet + water > glycerol + 3 fatty acids
What are the 6 major functions of the liver?
- destroys old red blood cells into part of bile 2. produces bile 3. stores glucose as glycogen & breaks down glycogen into glucose 4. produces urea from deamination 5. makes blood proteins from amino acids 6. detoxifies the blood
exocrine vs endocrine?
exo: to organ > enzyme
endo: to bloodstream > hormone
