A student studied how lactase affected three different liquids:
ordinary milk
milk that was lactose-free
sucrose solution.
A glucose indicator was used to test each liquid for glucose. A sample of every liquid was examined before and after treatment with lactase.
In the presence of glucose, the indicator became brown. In the absence of glucose, the indicator stayed blue.
Table 4.1 gives the test results.
(a(i))[3]
Explain the results for the three liquids in Table 4.1.
(a(ii))[4]
Using your knowledge of how temperature affects enzyme activity, explain why this was important.
(b(i))[2]
Suggest the dietary reasons for this advice.
(b(ii))[2]
Describe what a balanced diet means.
Worked solution & mark scheme
This 11-mark question has a full step-by-step worked solution and mark scheme. One marking point: “lactose is hydrolysed by lactase to produce glucose (and galactose)” …