Explain the induced-fit model of enzyme action, describing how the active site changes shape and how this lowers the activation energy of a metabolic reaction.
Students investigated the rate of hydrolysis of sucrose by the enzyme sucrase, which breaks down sucrose into glucose and fructose. They prepared several reaction mixtures, each containing:
Under these conditions, a water molecule is consumed as a reactant in each cleavage. Name the type of chemical reaction catalysed by sucrase.
The students allowed each reaction mixture to run for exactly 4 minutes before stopping it to measure the concentration of glucose produced. Suggest and explain one method the students could have used to halt the reaction immediately at 4 minutes.
The graph below shows the students' results:
Explain the relationship between glucose concentration produced and the initial concentration of sucrose shown in the graph.
Practise AQA A Level Biology Proteins with exam-style questions for A Level Biology. 22 questions covering General properties of proteins and Many proteins are enzymes, matched to the AQA A Level Biology (7402) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
