Which statement best describes the role of ATP in metabolic reactions?

A. ATP acts only in catabolic reactions.

B. ATP provides structural support to enzymes.

C. ATP supplies energy to drive endergonic reactions.

D. ATP is only used in carbohydrate metabolism.

How does enzyme specificity contribute to metabolic pathways?

A. It allows any substrate to bind to the enzyme.

B. It ensures that each enzyme catalyses multiple reactions.

C. It ensures the correct sequence of reactions by binding specific substrates.

D. It prevents the binding of cofactors and coenzymes.

What is the significance of compartmentalisation in metabolic pathways?

A. It decreases the efficiency of metabolic reactions.

B. It allows for simultaneous anabolic and catabolic reactions.

C. It prevents the synthesis of ATP.

D. It reduces the specificity of enzymes.

Which statement about the first and second laws of thermodynamics in biochemical reactions is correct?

A. The first law states that energy is lost as heat in every energy transfer.

B. The second law states that the total energy in a closed system remains constant.

C. The first law states that energy can be created and destroyed.

D. The second law states that every energy transfer increases the entropy of the universe.

How does feedback inhibition maintain metabolic homeostasis?

A. It increases the production of end products.

B. It prevents the use of intermediates in other pathways.

C. It accelerates the rate of enzyme activity.

D. The end product inhibits an earlier enzyme, regulating the pathway.

a) Explain how metabolic pathways can be both anabolic and catabolic, providing one example for each. [4]

b) Discuss the importance of compartmentalisation in metabolic pathways. [3]

a) Describe the nature of enzyme catalysis and the significance of the active site in enzymatic reactions. [3]

b) How do cofactors and coenzymes assist enzymatic reactions? Provide an example. [4]

a) Discuss the first and second laws of thermodynamics in the context of energy changes in biochemical reactions. [4]

b) Explain the role of ATP as the energy currency of the cell and how it is synthesised. [3]

a) Describe the role of intermediates in metabolic pathways and explain why they are important. [3]

b) How does end-product inhibition contribute to metabolic homeostasis? Provide an example. [4]

c) Discuss the factors that affect enzyme activity and how they influence metabolic reactions. [4]

a) Explain the concept of anabolic and catabolic pathways and how they are interconnected. [3]

b) Discuss the significance of compartmentalisation in maintaining the efficiency of metabolic pathways. [4]

c) How do the first and second laws of thermodynamics apply to the energy changes observed in cellular metabolism? [4]

What role do coenzymes play in enzymatic reactions?

A. They decrease the activation energy of the reaction.

B. They act as additional substrates for the enzyme.

C. They assist in the transfer of functional groups between substrates.

D. They alter the pH of the enzyme's active site.

Which of the following is a characteristic of anabolic pathways?

A. They break down complex molecules into simpler ones.

B. They release energy through the degradation of molecules.

C. They require energy to synthesise complex molecules from simpler ones.

D. They are not involved in the synthesis of macromolecules.

How does temperature affect enzyme activity?

A. Increased temperature always increases enzyme activity.

B. Decreased temperature changes the shape of the enzyme's active site.

C. Optimal temperature enhances the rate of collision between enzyme and substrate.

D. Temperature does not affect enzyme-substrate binding.

What is the role of intermediates in metabolic pathways?

A. They act as end products in every pathway.

B. They inhibit the activity of enzymes.

C. They are molecules that participate in the reaction but are not consumed.

D. They prevent the interconnectedness of metabolic pathways.

Which of the following is true regarding end-product inhibition?

A. It increases the concentration of intermediates in the pathway.

B. It is a form of positive feedback regulation.

C. It prevents the overaccumulation of the end product.

D. It activates the initial enzyme in the pathway.

a) Describe the structure of an enzyme’s active site and explain its role in substrate specificity. [3]

b) How do cofactors and coenzymes assist in enzymatic reactions? Provide an example for each. [4]

c) Explain the synthesis of ATP and its role in endergonic and exergonic reactions. [4]

a) Discuss the importance of intermediates in the interconnectedness of metabolic pathways. [3]

b) How does feedback inhibition, specifically end-product inhibition, regulate metabolic pathways? [4]

c) Discuss how the factors affecting enzyme activity can influence the rate and outcome of metabolic reactions. [4]

a) Explain how anabolic and catabolic pathways are interconnected in cellular metabolism, providing one example of each. [4]

b) Discuss the role of compartmentalisation in segregating metabolic pathways within a cell. Why is this important? [3]

c) Describe the nature of enzyme catalysis, focusing on the significance of the active site and substrate specificity. [4]

d) How do the first and second laws of thermodynamics relate to energy changes in biochemical reactions within a cell? [4]

a) Discuss the importance of intermediates in metabolic pathways and how they contribute to the interconnectedness of metabolism. [3]

b) Explain the concept of end-product inhibition and how it helps in maintaining metabolic homeostasis. Provide an example. [4]

c) How do cofactors and coenzymes assist enzymatic reactions? Illustrate with examples. [4]

d) Discuss the synthesis and role of ATP in endergonic and exergonic reactions within the cell. [4]

a) Explain the interconnectedness of metabolic pathways and why the availability of intermediates is crucial. [4]

b) Discuss how compartmentalisation within a cell contributes to the efficiency of metabolic pathways. Provide an example. [3]

c) Describe the factors that affect enzyme activity and explain how they can influence the rate of metabolic reactions. [4]

d) Relate the first and second laws of thermodynamics to the energy transformations observed in cellular metabolism. [4]