Principles of Biochemistry: Molecular
Structure, Reactions, and Cellular
Functions Exam Actual Questions and
Answers 2026
What is the main focus of biochemistry? -
correct answer ✅To explain biological processes at the molecular
and cellular levels.
What are the four main classes of biological molecules? -
correct answer ✅Amino acids, lipids, carbohydrates, and nucleic
acids.
Define enthalpy. -
correct answer ✅Enthalpy is the total heat content of a system.
What is entropy? -
correct answer ✅Entropy is a measure of the disorder or
randomness in a system.
What does free energy (ΔG) indicate? -
correct answer ✅Free energy indicates the spontaneity of a
reaction; a negative ΔG suggests a spontaneous process.
,Principles of Biochemistry: Molecular
Structure, Reactions, and Cellular
Functions Exam Actual Questions and
Answers 2026
What is the relationship between ΔH, ΔS, and ΔG? -
correct answer ✅ΔG = ΔH - TΔS, where T is the temperature in
Kelvin.
What is an endothermic reaction? -
correct answer ✅An endothermic reaction absorbs heat from the
surroundings.
What is an exothermic reaction? -
correct answer ✅An exothermic reaction releases heat to the
surroundings.
Define chemical equilibrium. -
correct answer ✅Chemical equilibrium is the state in which the
concentrations of reactants and products remain constant over
time.
What is the equilibrium constant (Keq)? -
correct answer ✅Keq is a ratio of the concentration of products
to reactants at equilibrium.
, Principles of Biochemistry: Molecular
Structure, Reactions, and Cellular
Functions Exam Actual Questions and
Answers 2026
What does ΔGo represent? -
correct answer ✅ΔGo is the standard free energy change for a
reaction under standard conditions.
What is energy coupling? -
correct answer ✅Energy coupling is the use of energy released
from one reaction to drive another reaction.
How does ATP hydrolysis facilitate energy coupling? -
correct answer ✅ATP hydrolysis releases energy that can be used
to drive endergonic reactions.
What is the significance of fermentation in biochemistry? -
correct answer ✅Fermentation is the conversion of sugars into
alcohol and CO2 by yeast, illustrating energy acquisition processes.
Who demonstrated that enzymes act as catalysts in fermentation? -
correct answer ✅Eduard Buchner demonstrated that enzymes
inside yeast catalyze fermentation reactions.
Structure, Reactions, and Cellular
Functions Exam Actual Questions and
Answers 2026
What is the main focus of biochemistry? -
correct answer ✅To explain biological processes at the molecular
and cellular levels.
What are the four main classes of biological molecules? -
correct answer ✅Amino acids, lipids, carbohydrates, and nucleic
acids.
Define enthalpy. -
correct answer ✅Enthalpy is the total heat content of a system.
What is entropy? -
correct answer ✅Entropy is a measure of the disorder or
randomness in a system.
What does free energy (ΔG) indicate? -
correct answer ✅Free energy indicates the spontaneity of a
reaction; a negative ΔG suggests a spontaneous process.
,Principles of Biochemistry: Molecular
Structure, Reactions, and Cellular
Functions Exam Actual Questions and
Answers 2026
What is the relationship between ΔH, ΔS, and ΔG? -
correct answer ✅ΔG = ΔH - TΔS, where T is the temperature in
Kelvin.
What is an endothermic reaction? -
correct answer ✅An endothermic reaction absorbs heat from the
surroundings.
What is an exothermic reaction? -
correct answer ✅An exothermic reaction releases heat to the
surroundings.
Define chemical equilibrium. -
correct answer ✅Chemical equilibrium is the state in which the
concentrations of reactants and products remain constant over
time.
What is the equilibrium constant (Keq)? -
correct answer ✅Keq is a ratio of the concentration of products
to reactants at equilibrium.
, Principles of Biochemistry: Molecular
Structure, Reactions, and Cellular
Functions Exam Actual Questions and
Answers 2026
What does ΔGo represent? -
correct answer ✅ΔGo is the standard free energy change for a
reaction under standard conditions.
What is energy coupling? -
correct answer ✅Energy coupling is the use of energy released
from one reaction to drive another reaction.
How does ATP hydrolysis facilitate energy coupling? -
correct answer ✅ATP hydrolysis releases energy that can be used
to drive endergonic reactions.
What is the significance of fermentation in biochemistry? -
correct answer ✅Fermentation is the conversion of sugars into
alcohol and CO2 by yeast, illustrating energy acquisition processes.
Who demonstrated that enzymes act as catalysts in fermentation? -
correct answer ✅Eduard Buchner demonstrated that enzymes
inside yeast catalyze fermentation reactions.
