Enzymes as Catalysts Remain Unchanged

Steps:

• Identify amylase as an enzyme that catalyzes the hydrolysis of starch into maltose using water.
• Recall that enzymes speed up reactions but are not consumed or produced.
• Determine the role of each substance: amylase (catalyst), water (reactant), maltose (product).
• Conclude that only the catalyst maintains constant molecule count.

Why A is correct:

• Enzymes like amylase act as catalysts, remaining unchanged in quantity per the definition of catalysis in chemical reactions.

Why the others are wrong:

• B. Water is a reactant consumed in the hydrolysis of starch.
• C. Maltose is a product formed, so its molecules increase.
• D. Duplicate of A, but not needed for analysis.

Final answer: A