Question

Which of the following statement is correct regarding enzymes?

• A. Enzymes are consumed permanently after reaction
• B. Enzymes lower activation energy of reaction
• C. Enzymes increase activation energy of reaction
• D. Enzymes are inorganic compounds

Hint:

Enzyme rule to remember: Enzymes speed up reactions by lowering activation energy. They are biological catalysts and are not consumed permanently during reactions.

Answer 1

The Correct Option is B

Concept: Enzymes are biological catalysts that accelerate biochemical reactions occurring inside living organisms. Almost every metabolic reaction inside cells depends upon enzymes. A catalyst is a substance that increases reaction speed without being permanently consumed during the reaction. For any chemical reaction to begin, reactant molecules must overcome an energy barrier called activation energy. Enzymes function by lowering this activation energy barrier so reactions proceed rapidly under normal physiological conditions.

Step 1: Understand what activation energy means.
Before reactants can convert into products, molecules require a minimum amount of energy. This minimum threshold energy is called activation energy. It allows reactant molecules to reach a transition state from where products can form. If activation energy is very high, reaction occurs slowly. If activation energy decreases, reaction speed increases. Thus activation energy directly controls reaction rate.

Step 2: Understand role of enzymes in biochemical reactions.
Enzymes bind temporarily with substrate molecules at a specialized region called active site. This enzyme-substrate complex helps arrange reactants in favorable orientation. As a result, less energy is required for molecules to react. Therefore enzyme reduces activation energy. Mathematically the relationship can be summarized as \[ \text{Lower activation energy} \rightarrow \text{Faster reaction} \] Hence enzyme accelerates reaction speed.

Step 3: Check incorrect options one by one.
Option (A) It says enzymes are permanently consumed. This is incorrect because enzymes remain chemically unchanged after reaction and can be reused repeatedly. Option (C) It says enzymes increase activation energy. This is incorrect because increased activation energy would slow reactions. Enzymes do the opposite. Option (D) It says enzymes are inorganic compounds. This is incorrect because most enzymes are proteins, which are organic biomolecules. Hence options A, C and D are wrong.

Step 4: Identify correct statement and conclude.
Option (B) states enzymes lower activation energy. This exactly describes catalytic action of enzymes. Therefore correct answer is \[ \boxed{\text{Enzymes lower activation energy of reaction}} \] Hence \[ \boxed{\text{Option (2)}} \]