Biology 9700 · AS & A Level · Transport mechanisms
Transport mechanisms — practice question
Amylase is an enzyme that speeds up the hydrolysis of starch to reducing sugars. A student performed an experiment to investigate starch hydrolysis with immobilised amylase. Fig. 6.1 shows the apparatus used in the investigation. The alginate beads were all identical in size. Both taps were opened so that the starch solution moved down the column and the product could be collected. The product was then tested for reducing sugar and starch.
(a)[3]
The results showed that the beaker product contained reducing sugar and starch. Using Fig. 6.1, describe a method that would let the student use the immobilised amylase to obtain a product containing only reducing sugar.
(b)[1]
In this investigation, one controlled variable is the size of the alginate beads. Suggest one reason why using larger or smaller alginate beads in the column would change the results obtained.
Worked solution & mark scheme
This 4-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Make the contact time between starch and immobilised amylase longer, for example by closing the lower tap or by reducing the flow rate.” …