Question

a graph showing a reaction in the body under two different conditions is shown below. which statement explains why the reaction with the lower peak?
a. a gas escaped during the reaction with the lower peak, meaning less energy was needed.
b. an enzyme was used in the reaction with the lower peak, meaning less energy was needed.
c. there were less reactants during the reaction with the lower peak, meaning more energy was needed.
d. it was colder during the reaction with the lower peak, meaning more energy was needed.

Explanation:

Enzymes are biological catalysts. Catalysts lower the activation energy (the peak in the energy - reaction diagram) required for a reaction to occur. A lower peak means less energy is needed for the reaction to proceed. Option A is incorrect because gas escape is not related to the energy peak. Option C is wrong as the amount of reactants does not directly affect the activation energy peak. Option D is incorrect because temperature (being "colder") affects reaction rate through other mechanisms (like molecular motion) and not by lowering the activation energy peak in the way shown (enzymes lower activation energy).

Answer:

B. An enzyme was used in the reaction with the lower peak, meaning less energy was needed.