Final answer:
Increasing the temperature of an enzyme-controlled reaction by 10°C usually increases the reaction rate, assuming the temperature was initially below the enzyme's optimal range.
Step-by-step explanation:
When the temperature of an enzyme-controlled reaction is increased by 10°C, the rate of reaction typically increases. This rise in temperature leads to more molecules having energy greater than the activation energy, thus, increasing the rate at which reactions occur. However, there is a threshold beyond which further temperature increase can cause the enzyme to denature, which will drastically decrease the reaction rate.
Since enzymes have an optimum temperature at which they function most efficiently, if the initial temperature was below this optimum, increasing the temperature by 10°C will likely increase the rate of reaction.