BIOCHEMISTRY
ENZYMES AND METABOLISM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the substrate and enzyme are joined permanently
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the enzyme can start the reaction again once the products are released
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the enzyme cannot be used in the reaction again
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the enzyme is destroyed in the chemical reaction
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Detailed explanation-1: -Enzymes are not reactants and are not used up during the reaction. Once an enzyme binds to a substrate and catalyzes the reaction, the enzyme is released, unchanged, and can be used for another reaction. This means that for each reaction, there does not need to be a 1:1 ratio between enzyme and substrate molecules.
Detailed explanation-2: -One of the hallmark properties of enzymes is that they remain ultimately unchanged by the reactions they catalyze. After an enzyme has catalyzed a reaction, it releases its product(s) and can catalyze a new reaction.
Detailed explanation-3: -Enzymes let chemical reactions in the body happen millions of times faster than without the enzyme. Because enzymes are not part of the product, they can be reused again and again.
Detailed explanation-4: -The enzyme reduces the energy barrier required to activate the substrate, allowing more substrates to become activated, which increases the rate of product formation. Note that the energy difference between the substrate and the product is not changed by the enzyme.
Detailed explanation-5: -Enzymes are biological catalysts. Catalysts lower the activation energy for reactions. The lower the activation energy for a reaction, the faster the rate. Thus enzymes speed up reactions by lowering activation energy.