Which of the following best describes the function of an enzyme in living organisms?
It acts as a biological catalyst to speed up chemical reactions without being consumed.
It is a reactant that is consumed to provide energy for a reaction.
It acts as an inhibitor to prevent metabolic processes from occurring too quickly.
It is an organic nutrient that serves as a direct source of cellular power.
31 exam-style questions on OCR GCSE Chemistry Controlling reactions. Each one has a worked solution and a mark scheme showing where the marks go.