Check your understanding 1. Look at your results in Table 1. a. At which of the pHs you tested was the enzyme working most efficiently?
[1 mark]
......................................................................................................................................................... b. How could you find a more exact optimum pH?
[1 mark]
......................................................................................................................................................... c. At which pH values does your amylase not work?
[1 mark]
......................................................................................................................................................... 2. List two control variables that were controlled during this experiment.
[2 marks]
......................................................................................................................................................... .........................................................................................................................................................
Exam-style questions 1. Lipase is a digestive enzyme that breaks lipids (fats) down into fatty acids and glycerol. Full fat milk has a pH of 6.5. a. Predict what will happen to the pH of full fat milk as lipids are broken down. Explain your prediction.
[2 marks]
......................................................................................................................................................... ......................................................................................................................................................... b. A student wants to investigate the optimum temperature of lipase. Describe a method the student could use to find the optimum temperature of lipase. [6 marks] ......................................................................................................................................................... ......................................................................................................................................................... ......................................................................................................................................................... ......................................................................................................................................................... ......................................................................................................................................................... ......................................................................................................................................................... ......................................................................................................................................................... .........................................................................................................................................................
AQA GCSE (9–1) Combined Science: Trilogy Required Practicals Lab Book
14
Š HarperCollinsPublishers Limited 2018