The enzyme invertase catalyses the breakdown of sucrose to glucose and fructose. Three different enzyme inhibitors of invertase X, Y and Z were investigated. The percentage inhibition of invertase was measured at different concentrations of inhibitor. The graph shows the result of the investigation. [Graph showing percentage inhibition vs. inhibitor concentration for inhibitors X, Y, Z] Which are valid conclusions from these results? 1 The higher the concentration of inhibitor X, the less sucrose is broken down. 2 The production of glucose and fructose using inhibitor Y is higher than when inhibitor Z is used. 3 The production of glucose and fructose at an inhibitor concentration of 2 arbitrary units is lower than at an inhibitor concentration of 4 arbitrary units, for all inhibitors.

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