Required Practicals - Enzymes

Question 1

What is the goal of the enzyme practical?

Answer 1

To investigate the effect of pH on the rate of reaction of amylase enzyme.

Question 2

What is the apparatus for the enzyme practical?

Answer 2

-10 test tubes
-test tube rack
-water bath
-thermometer
-spotting tile
-5cm3 measuring cylinder
-pasteur pipettes
-glass rod
-stop clock
-starch solution
-amylase solution
-iodine solution
-labelled buffered solutions at a range of pH values
-labels

Question 3

What is the method for the enzyme practical?

Answer 3

-heat the water bath to 35 degrees
-put 2cm3 of each solution into individual, separate test tubes. Label each tube with its pH
-label 5 test tubes ‘starch’ and add 4cm3 of starch solution into each tube.
-put a thermometer in one of the starch test tubes to monitor the temperature.
-add 10cm3 of Amylase solution into another tube and label it ‘amylase’
-put all test tubes into the water bath
-allow the solutions to reach 35 degrees
-while the solutions are reaching the required temp, put one drop of iodine into each depression on the spotting tile.
-put a drop of starch solution in the first depression. This is the zero time mixture.
-when all tubes habe reached 35 degress take one of the starch tubes and add the 2cm3 of the first pH buffered solution. Stir the mixture with a glass rod
-use the pipette to add 2cm3 of amylase to the mixture. Start the stopclock as you add the amylase, stir with a glass rod.
-after 10 seconds, remove one drop of the mixture with a glass rod.
-put this drop on the second depression of the spotting tile.
-rinse the glass rod with water
-every 10 seconds, use the rod to remove one drop of mixture. Put each drop onto the iodine in the next depression on the spotting tile
-keep sampling every 10 seconds until the iodine doesn’t change colour
-repeat with each pH solution

Question 4

What are enzymes?

Answer 4

Biological catalysts that speed up a reaction without being used up.