enzymes and digestion
enzymes
proteins
biological catalysts that speed up the rate of a reaction without being used up itself
active site
allows substrate to fit into it
as each enzyme has a specific shape -----each enzyme can only catalyse a specific reaction
lock and key model
small make large
large break into small
substrate molecules fit into the active site
an enzyme-substrate complex is formed which allows bonds to be formed between the molecules
makes bigger molecule
large substrate molecule fits into the active site
enzyme-substrate complex is formed - allows bonds to break
2 smaller product molecules made
best
temperature
pH
concentration of enzyme
for many enzymes it'll be around 37*C (body temperature)
own optimum pH
kinetic energy
collisions
rate of reaction
^^ active site= irreversibly destroyed -- enzyme = denatured
lipase = 8
protease = 2
above or below optimum pH = denatured
start
end
increasing the enzyme concentration has no effect on the rate of reaction. substrate = LF
the more enzyme there are the faster the rate of the reaction. cuz there are more active sites for the substrate to fit into
enzyme inhibitors
similar shape to substrate
fits partially into the active site X the substrate
reduce or slow down the rate of reaction
digestion
is the breaking down large complex insoluble molecules into small soluble molecules
digestive enzymes
made in glands and lining of the gut
carbohydrase
amylase
protease
lipase
carbohydrate
simple sugar-glucose
starch
simple sugar-glucose
protein
amino acids
fats/lipids
glycerol & 3 fatty acids
pH
alkaline
acidic
stomach
kills bacteria in food
provides a low pH for enzymes to work
small intestine
bile
bile is produced by liver stored in gall bladder >> small intestine
emulsifies fats- larger surface area for lipase to work
neutralises the acid that was added to the food in stomach
provides alkaline conditions for enzymes