3
Question
During glycolysis, the final step is the conversion of phosphoenolpyruvate to pyruvate with the help of an enzyme. Can you pick which of the following curves is with and without the presence of enzyme?
During glycolysis, the final step is the conversion of phosphoenolpyruvate to pyruvate with the help of an enzyme. Can you pick which of the following curves is with and without the presence of enzyme?
Open in App
Solution
The correct option is D Exothermic reaction with energy A in presence of enzyme and B in the absence of enzyme
The pathway of the breakdown of glucose into pyruvic acid is termed as glycolysis. The final step of glycolysis is the conversion of phosphoenolpyruvate to pyruvate with the help of the enzyme pyruvate kinase.
Activation energy is defined as the minimum amount of extra energy required by reacting molecules to get converted into the product. In enzymatically catalysed reactions, enzymes lower the amount of activation energy required to start the reaction.
Exothermic reactions are those that release energy, usually in the form of heat while endothermic reactions are those that require energy usually in the form of heat to proceed.
As shown in the graph, the energy of the pyruvate formed is lower than that of the phosphoenolpyruvate. It means that during the course of the reaction, energy is released. Hence, the reaction represented by both the curve is that of an exothermic process.
We see that curve A has a peak lower than that of curve B. This peak refers to the transition state of the substrate being converted into the product. The difference in the energy level of the substrate and transition state is the activation energy required to start the reaction. We observe that this difference is the least in curve A, implying that the activation energy is also reduced. Hence, it can be said that curve A represents the reaction in the presence of the enzyme. Whereas curve B is the reaction without the enzyme.
The pathway of the breakdown of glucose into pyruvic acid is termed as glycolysis. The final step of glycolysis is the conversion of phosphoenolpyruvate to pyruvate with the help of the enzyme pyruvate kinase.
Activation energy is defined as the minimum amount of extra energy required by reacting molecules to get converted into the product. In enzymatically catalysed reactions, enzymes lower the amount of activation energy required to start the reaction.
Exothermic reactions are those that release energy, usually in the form of heat while endothermic reactions are those that require energy usually in the form of heat to proceed.
As shown in the graph, the energy of the pyruvate formed is lower than that of the phosphoenolpyruvate. It means that during the course of the reaction, energy is released. Hence, the reaction represented by both the curve is that of an exothermic process.
We see that curve A has a peak lower than that of curve B. This peak refers to the transition state of the substrate being converted into the product. The difference in the energy level of the substrate and transition state is the activation energy required to start the reaction. We observe that this difference is the least in curve A, implying that the activation energy is also reduced. Hence, it can be said that curve A represents the reaction in the presence of the enzyme. Whereas curve B is the reaction without the enzyme.
Suggest Corrections
1
Similar questions
