2.2 enzymes Flashcards
what is an enzyme?
biological catalyst, speeds up rate of chemical reaction
how do enzymes have an adapted shape?
long chains of amino acids, folded to make special shape vital to enzyme function
what is the lock and key theory?
- substrate to be catalysed fits into active site of enzyme
- substrate and enzyme have complimentary shape
- substrate split into products, broken down by catalyst,
what is the active site of an enzyme?
region on an enzyme protein or other substance binds to during reaction
what is protein broken down by?
where is this enzyme found?
- protease
- found in stomach, pancreas, small intestine
what are lipids broken down by?
where is this enzyme found?
what are lipids broken down into?
- lipase
- pancreas, small intestine
- one molecule glycerol, 3 molecules fatty acids
what are carbohydrates broken down by?
-carbohydrase
what is starch broken down by?
where is this enzyme found?
-amylase
- salivary glands, pancreas
what is bile?
where is bile made?
where is bile stored?
- speeds up digestion of lipids
- liver
- gallbladder
what does bile do?
- converts large lipid droplets into small lipid droplets
- bile emulsifies lipid, increase surface area of lipid droplets, increase rate of lipid breakdown by lipase
-alkaline; neutralises stomach acid
what is the effect of high temperature on enzymes?
what is optimum temperature?
- rate of reaction increases as temperature increases
- at a certain temperature enzyme starts to denature (active site of enzyme permanently changes) meaning substrate no longer fits into enzyme
- 37 degrees
what is the effect of low temperature on enzymes?
- enzyme and substrate have less energy, move slower, collide less, reaction slows down
What does PH do to an enzyme?
- affects the forces that hold the folded chains in place
What happens if there is a change in PH?
- change in shape of molecules
