enzymes Flashcards
what is an enzyme
a biological catalyst that speeds up reactions
what is the lock and key model
1-enzymes are biological catalysts
2-the active site of the enzyme has a complimentary shape to the shape of the substrate
3-when the enzyme collides with the substrate the right shape to it they bind to its active site
4-the substrate is then turned into products and the enzyme is reusable
what does lipids bind with
lipase to make glycerol and fatty acids
what does protein bind with
protease to make amino acids
what does starch bind with
amylase to make maltose (sugars)
what is the effect of temperature on an enzyme
1-if it becomes too hot the enzyme can become denatured- the active site is no longer complimentary to the catalyst
2- if it is too cold there may not be enough kinetic energy therefore very few collisions
what does optimum temperature mean
the rate of reaction is at its maximum and if it gets any warmer the enzyme will become denatured
affect of ph on an enzyme
if the ph is too high or too low the enzyme will become denatured
enzyme required practical
1- heat your water bath to 35 degrees
2- put 2cm cubed of each solution (ph4-8) in separate test tubes and label each tube with the right PH
3-Label 5 test tubes starch and add 4cm cubed of starch solution
4- add 10cm cubed of amylase into another test tube
5- place them all in the water bath and measure with a thermometer until 35 degrees is reached
6-set up 2 dropping tiles
7- place a drop of iodine in each well
8- pour the amylase into the starch and begin the timer
9- every 30 seconds take a drop of the liquid using a pipette and put in the tile
10- if starch is present the solution will keep turning blue back
11- keep repeating every 30 seconds until there is no longer any starch present and the tiles aren’t turning blue/black but orange/brown instead
what colour does iodine turn if starch is present
blue black
what colour does iodine turn if starch isn’t present
orange brown
