Enzymatic Reactions - PRACTICAL

Question 1

What does the enzyme amylase catalyse?

Answer 1

The breakdown of starch to maltose

Question 2

How can starch be detected?

Answer 2

Using iodine solution which changes from browny-orange to blue-black in the presence of starch

Question 3

What is the first step in investigating how pH affects amylase activity?

Answer 3

Put a drop of iodine solution into every well of a spotting tile

Question 4

What temperature should the water be heated to in the experiment?

Answer 4

35 °C

Question 5

What is added to the boiling tube after heating the water?

Answer 5

1 cm³ of amylase solution and 1 cm³ of a buffer solution with a pH of 5

Question 6

What should be done after adding the starch solution to the boiling tube?

Answer 6

Immediately mix the contents and start a stop clock

Question 7

How often should samples be taken from the boiling tube?

Answer 7

Every 30 seconds

Question 8

What indicates that starch is no longer present in the solution?

Answer 8

When the iodine solution remains browny-orange

Question 9

What must be controlled to ensure a fair test in the experiment?

Answer 9

Concentration and volume of amylase solution

Question 10

How is the rate of reaction calculated?

Answer 10

Rate = amount of change / time taken

Question 11

If the time taken for amylase to break down starch at pH 8 is 90 seconds, what is the rate of reaction?

Answer 11

11.11 g/s

Question 12

Fill in the blank: Amylase breaks down starch to _______.

Answer 12

maltose

Question 13

True or False: Iodine solution turns blue-black in the presence of glucose.

Answer 13

False