STPM S1 Biology Quiz - Enzymes

1. What are enzymes?

• Synthetic chemicals used in manufacturing

• Inorganic compounds found in rocks

• Biological molecules that act as catalysts

• Large biological structures

2. Name the type of biological molecule that enzymes are.

• Nucleic acid

• Protein

• Lipid

• Carbohydrate

3. What is the function of enzymes in living organisms?

• Cause mutations in DNA

• Have no effect on chemical reactions

• Slow down chemical reactions

• Speed up chemical reactions

5. How do enzymes speed up chemical reactions?

• By lowering the activation energy

• By changing the pH of the environment

• By inhibiting the reaction

• By increasing the activation energy

6. What factors can affect the activity of enzymes?

• Color of the enzyme

• Temperature, pH, substrate concentration, enzyme concentration, presence of inhibitors

• Distance from the equator

• Time of day

7. Define enzyme inhibition and provide an example.

• Enzyme inhibition is the process where an enzyme is activated by a molecule binding to it. An example is the activation of pepsin by hydrochloric acid in the stomach.

• Enzyme inhibition is the process where the activity of an enzyme is hindered by a molecule binding to it. This can be reversible or irreversible.

• Enzyme inhibition is the process where an enzyme's activity is unaffected by any external factors. An example is the action of amylase in breaking down starch.

• Enzyme inhibition is the process where an enzyme's activity is enhanced by a molecule binding to it. An example is the enhancement of catalase activity by hydrogen peroxide.

8. Describe the process of enzyme denaturation.

• Enzyme denaturation occurs when the protein structure of the enzyme is disrupted, leading to loss of its function.

• Enzyme denaturation leads to an increase in the enzyme's activity.

• Enzyme denaturation occurs when the enzyme becomes more efficient at its function.

• Enzyme denaturation is the process of enhancing the stability of the enzyme structure.

9. Explain the concept of enzyme specificity.

• The ability of an enzyme to recognize and bind to any substrate, and then catalyze any reaction.

• The ability of an enzyme to recognize and bind to a specific substrate, and then catalyze a specific reaction.

• Enzyme specificity refers to the ability of an enzyme to recognize and bind to multiple substrates at the same time.

• Enzyme specificity is the ability of an enzyme to catalyze a wide range of reactions without any preference for a specific substrate.

10. Discuss the role of enzymes in metabolism.

• Enzymes have no role in metabolism.

• Enzymes are only found in plants, not in metabolism.

• Enzymes slow down chemical reactions in metabolism.

• Enzymes speed up chemical reactions in metabolism.

11. What is the effect of temperature on enzyme activity?

• Temperature has no effect on enzyme activity

• Enzyme activity increases with temperature until it reaches an optimum, then decreases

• Enzyme activity decreases with temperature until it reaches an optimum, then increases

• Enzyme activity is not affected by temperature changes