Enzymes act as biological catalysts.
Which statement describes a biological catalyst?
It increases reaction rate without being used up.
It increases reaction rate by being used up.
It decreases reaction rate without being used up.
It decreases reaction rate by being used up.
44 exam-style questions on Edexcel GCSE Biology 1.3 Enzymes, covering 1.3.1 Mechanism of enzyme action, 1.3.2 Denaturation of enzymes, 1.3.3 Factors affecting enzyme activity, and 1.3.4 Measuring energy in food by calorimetry. Each one has a worked solution and a mark scheme showing where the marks go.