Question

Which of the following statements is true about enzymes?

Question 3 options:

enzymes can only be used one time


enzymes increase the activation energy of a reaction


enzymes are specific to their substrate


one enzyme can be used in many different types of reactions

Answer 1

Enzymes are specific to their substrate and work by lowering the activation energy of reactions, which allows them to accelerate chemical processes without being consumed in the reaction.

Step-by-step explanation:

The correct statement about enzymes is that enzymes are specific to their substrate. Enzymes are biological catalysts that accelerate chemical reactions by lowering the activation energy required for the reaction to occur. Contrary to increasing the activation energy, they reduce it, thus making reactions proceed more quickly than they would without the enzyme. Also, while enzymes are not used up in the reaction and can be used multiple times, their use is not universal; rather, they typically catalyze specific types of reactions. Some enzymes exhibit absolute specificity, binding to only one particular substrate, while others have group specificity or relative specificity for a certain type of bond or chemical group within various substrates.

Answer 2

The answer is B or #2, enzymes are very specific to their substrate.

Step-by-step explanation:

In an enzyme activity, the substrate must bind with the enzyme to become a catalyst of a chemical reaction. And most enzymes are highly specific particularly to the nature of the substrate they bind to. Substrate specificity is one of the most essential distinctive features of enzymes. Enzymes are biological catalysts which speed up biochemical reactions. According to the most widely accepted theory, enzymes bind to the substrate molecule and form a transition state. During the progress of a reaction the substrates are separated from products by an energy barrier which the substrates need to cross. This energy barrier is called as the activation energy. The activation energy barrier in case of transition state is far less as compared to the activation energy barrier in absence of enzymes. Hence, the rate of reaction is more in case of enzyme catalyzed reactions due to the formation of transition state and lower activation energy requirement. This change is brought about by an apparent increase in energy level of substrate molecules.