AQA - Biology - Enzymes

What is the primary structure of an enzyme composed of?

• Nucleotides

• Amino acids

• Fatty acids

• Monosaccharides

Which part of the enzyme is responsible for its catalytic activity?

• Substrate

• Active site

• Inhibitor

• Coenzyme

How do enzymes speed up chemical reactions?

• By increasing the temperature

• By lowering the activation energy

• By increasing the concentration of reactants

• By changing the pH of the environment

What is meant by enzyme specificity?

• Enzymes can act on any substrate

• Enzymes are specific to a particular substrate

• Enzymes can only function at a specific temperature

• Enzymes are specific to a particular pH

Which of the following best describes the 'lock and key' model of enzyme action?

• The enzyme changes shape to fit the substrate

• The substrate changes shape to fit the enzyme

• The enzyme and substrate fit together without changing shape

• The enzyme and substrate do not fit together

What happens to an enzyme when it is denatured?

• It becomes more active

• It loses its specific shape

• It binds more tightly to the substrate

• It becomes a different enzyme

Which factor does NOT affect enzyme activity?

• Temperature

• pH

• Substrate concentration

• Colour of the enzyme

What is the term for a non-protein molecule that assists an enzyme in its function?

• Substrate

• Inhibitor

• Coenzyme

• Catalyst