Year 12 Biology: Spring Term 2022

Which of the following bonds can be found in enzyme?

• Disulphide bridges, Hydrogen bonds, Ionic bonds
• Hydrogen bonds, Peptide bonds, Ionic bonds
• Disulphide bridges, Peptide bonds, Ionic bonds
• Disulphide bridges, Hydrogen bonds, Peptide bonds

Which type of inhibition involves an early enzyme in a metabolic pathway being inhibited

• End product
• competitive
• non-competitive
• inhibitory

A molecule binds to an enzyme and decreases the Vmax of an enzyme. This is called:

• Allosteric Inhibition

• Competitive Inhibition

• Allosteric Activation

• Non-competitive inhibition

Consider the following: “Succinate dehydrogenase catalyzes the conversion of succinate to fumarate. The reaction is inhibited by malonic acid, which resembles succinate but cannot be acted upon by succinate dehydrogenase. Increasing the ratio of succinate to malonic acid reduces the inhibitory effect of malonic acid”. Which of the following is correct?

• Succinate is the substrate, and fumarate is the product
• Succinate dehydrogenase is the enzyme, and fumarate is the substrate
• Fumarate is the substrate, and malonic acid is a non-competitive inhibitor
• Succinate dehydrogenase is the enzyme, and malonic acid is the substrate

A metabolic pathway consists of ...

• a series of chemical reactions
• a series of enzymes
• a series of biological reactions
• a series of physical reactions

When a molecule can occupy the same active site as the substrate, a situation called __________________ can result

• Competitive lnhibition
• Feedback Inhibition
• Non-Competitive Inhibition
• Allosteric Regulation

Which inorganic ion can act as a cofactor for amylase?

• Cl⁻

• PO₄³⁻

• OH⁻

• HCO₃⁻

Which of the following factors does not affect the shape of the active site of an enzyme?

• a drop in temperature
• binding of substrate
• non-competitive inhibitor
• an increase in pH

Zinc ions are necessary for the enzyme carbonic anhydrase to work. Which statement correctly describes the nature and function of zinc ions in their interaction with carbonic anhydrase?

• inorganic ions and prosthetic groups
• inorganic ions and coenzymes
• vitamins and prosthetic groups
• vitamins and coenzymes

Which of the following is an incorrect statement about enzymes?

• extracellular enzymes are produced outside the cell
• amylase and trypsin catalyse extracellular reactions
• catalase catalyses intracellular reactions
• intracellular enzymes work inside the cell