PORTAGE LEARNING • GENEVA COLLEGE
BioChem 210
Final Examination
Biochemistry •
Comprehensive Coverage of All Eight Modules
Total Questions 150 (Multiple Choice, A–D)
Sections 9 sections covering all 8 modules
Cognitive Mix 30% Recall • 50% Application • 20% Analysis
Question Style 70% Scenario-based • 20% Direct recall • 10% Calculation
Aligned Curriculum 2026–2027 Portage Learning / Geneva College CHEM 210
Examination Instructions
This comprehensive final examination consists of 150 multiple-choice questions distributed
across nine sections covering all eight modules of the CHEM 210 biochemistry curriculum.
Each question has exactly one correct answer (A, B, C, or D). Correct answers are marked
with [CORRECT] and accompanied by a comprehensive biochemistry rationale.
Section 9 (Questions 141–150) requires cross-module integrated reasoning across
metabolism, bioenergetics, and clinical scenarios.
All content is aligned with the 2026–2027 Portage Learning / Geneva College CHEM 210
curriculum standards and biochemistry competencies.
A+ Verified Comprehensive Final Examination • 150 Questions with Comprehensive Rationales
BioChem 210 Final Examination • 2026/2027 Edition
,BioChem 210 Final Exam • Biochemistry Geneva College • Portage Learning • 2026/2027
Section 1 • Module 1: Biochemistry Fundamentals, Water, pH, Buffers, Amino Acids & Protein Structure
Questions 1–25
Q1: Biochemistry is best defined as which of the following?
A. The study of cellular anatomy under a microscope
B. The study of the chemical basis of life [CORRECT]
C. The study of organic reaction mechanisms only
D. The study of physical forces in biological systems
Correct Answer: B
Rationale: Biochemistry is the study of the chemical substances and reactions that occur in living organisms, encompassing
structure, function, and metabolism of biomolecules. It bridges biology and chemistry by explaining life processes in
molecular terms. The other options either describe other disciplines (anatomy, organic chemistry, biophysics) or are too
narrow.
Q2: Which set of elements is collectively referred to by the acronym CHONPS in biochemistry?
A. Calcium, Hydrogen, Oxygen, Nickel, Phosphorus, Sulfur
B. Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur [CORRECT]
C. Carbon, Helium, Oxygen, Nitrogen, Potassium, Sodium
D. Chlorine, Hydrogen, Oxygen, Nitrogen, Phosphorus, Silicon
Correct Answer: B
Rationale: CHONPS stands for Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, and Sulfur—the six elements that
constitute the vast majority of biological molecules. Carbon forms the backbone of organic compounds, N is essential for
amino acids and nucleotides, P for nucleic acids and ATP, and S for cysteine/methionine. The other options include
non-biological or incorrect elements.
Q3: A solution has a hydrogen ion concentration of 1 × 10 ⁴ M. What is the pH of this solution?
A. pH 4 [CORRECT]
B. pH 10
C. pH 0.0001
D. pH 14
Correct Answer: A
Rationale: By definition, pH = −log[H ]. Substituting [H ] = 1 × 10 ⁴ M gives pH = −log(10 ⁴) = 4. This solution is
moderately acidic, well below physiological pH (~7.4). The pH scale is logarithmic, so each unit represents a tenfold change
in hydrogen ion concentration.
Q4: Normal human blood is maintained at a pH of approximately 7.4. A patient with metabolic acidosis has a blood
pH of 7.1. How does the hydrogen ion concentration in this patient compare to normal?
A. It is half as high
B. It is twice as high [CORRECT]
C. It is 0.3 times as high
D. There is no change in [H ]
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,BioChem 210 Final Exam • Biochemistry Geneva College • Portage Learning • 2026/2027
Correct Answer: B
Rationale: Because the pH scale is logarithmic (base 10), a decrease of 0.3 pH units corresponds to approximately a twofold
increase in [H ]. Going from pH 7.4 to 7.1 is a 0.3-unit decrease, so [H ] roughly doubles. This is why even small pH
changes are clinically significant: they reflect substantial changes in hydrogen ion concentration.
Q5: The Henderson-Hasselbalch equation relates pH, pKa, and the ratio of base to acid forms of a buffer. Which of
the following is the correct form of this equation?
A. pH = pKa + log([HA]/[A ])
B. pH = pKa + log([A ]/[HA]) [CORRECT]
C. pH = pKa − log([A ]/[HA])
D. pH = pKa × log([A ]/[HA])
Correct Answer: B
Rationale: The Henderson-Hasselbalch equation is pH = pKa + log([A ]/[HA]), where [A ] is the deprotonated (base)
form and [HA] is the protonated (acid) form. When [A ] = [HA], the log term equals zero and pH = pKa, the point of
maximum buffering capacity. Reversing the ratio or using subtraction would give incorrect pH predictions.
Q6: The bicarbonate buffer system is the primary buffer in human blood. Which sequence correctly represents the
components of this buffer system?
A. CO₂ + H₂O H₂CO₃ H + HCO₃ [CORRECT]
B. N₂ + H₂O NH₃ NH₄ + OH
C. O₂ + H₂O H₂O₂ H + HO₂
D. CO₂ + N₂ HCN H + CN
Correct Answer: A
Rationale: In the bicarbonate buffer system, CO₂ produced by cellular metabolism reacts with water to form carbonic acid
(H₂CO₃), which dissociates into H and bicarbonate (HCO₃ ). This system is especially effective because its acid component
(CO₂) is regulated by respiration and its base component (HCO₃ ) by the kidneys, providing powerful physiological control
of blood pH.
Q7: Which statement best defines pKa for a weak acid?
A. The pH at which the acid is fully protonated
B. The pH at which half of the acid molecules are protonated and half are deprotonated [CORRECT]
C. The pH at which the acid is fully deprotonated
D. The concentration of acid in solution
Correct Answer: B
Rationale: pKa is the pH at which a weak acid is 50% dissociated, meaning [HA] = [A ]. At this point, the
Henderson-Hasselbalch equation reduces to pH = pKa. pKa is an intrinsic property of a weak acid (independent of
concentration) that quantifies its tendency to donate a proton: lower pKa values indicate stronger acids.
Q8: A biochemist is preparing a buffer and needs it to be most effective at pH 6.5. The pKa values of several weak
acids are listed. Which acid would make the best buffer component?
A. Acid with pKa = 4.2
B. Acid with pKa = 5.4
C. Acid with pKa = 6.3 [CORRECT]
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, BioChem 210 Final Exam • Biochemistry Geneva College • Portage Learning • 2026/2027
D. Acid with pKa = 8.5
Correct Answer: C
Rationale: Buffers function most effectively within ±1 pH unit of their pKa, where both protonated and deprotonated forms
are present in appreciable concentrations. For a target pH of 6.5, an acid with pKa = 6.3 is ideal because the desired pH falls
well within the buffering range (5.3–7.3). The other options fall outside this optimal range and would provide little buffering
capacity at pH 6.5.
Q9: The general structure of an α-amino acid consists of a central α-carbon bonded to four groups. Which
combination correctly identifies these four substituents?
A. An amino group, a carboxyl group, a hydroxyl group, and an R-group
B. An amino group, a carboxyl group, a hydrogen atom, and an R-group [CORRECT]
C. An amino group, two carboxyl groups, and an R-group
D. Two amino groups, a hydrogen atom, and an R-group
Correct Answer: B
Rationale: All 20 standard α-amino acids share a common structure: the α-carbon is bonded to an amino group (−NH₃ at
physiological pH), a carboxyl group (−COO at physiological pH), a hydrogen atom, and a variable R-group (side chain).
The R-group is what distinguishes one amino acid from another and determines its chemical properties.
Q10: At physiological pH (~7.4), the amino group and carboxyl group of a free amino acid exist predominantly in
which ionic forms?
A. −NH₂ and −COOH
B. −NH₃ and −COO [CORRECT]
C. −NH₂ and −COO
D. −NH₃ and −COOH
Correct Answer: B
Rationale: At physiological pH, amino acids exist as zwitterions: the amino group is protonated (−NH₃ , pKa ~9–10) and the
carboxyl group is deprotonated (−COO , pKa ~2). This gives the amino acid a net charge of zero (for uncharged side
chains) but with both positive and negative charges present. The zwitterionic form is responsible for the high melting point
and crystalline nature of amino acids.
Q11: Which of the following amino acids is classified as nonpolar (hydrophobic)?
A. Serine
B. Lysine
C. Leucine [CORRECT]
D. Aspartate
Correct Answer: C
Rationale: Leucine has an isobutyl side chain that is purely hydrocarbon, making it strongly nonpolar and hydrophobic.
Serine has a hydroxyl group (polar uncharged), lysine has a positively charged amino group (basic), and aspartate has a
negatively charged carboxylate (acidic). Nonpolar amino acids such as leucine, valine, isoleucine, and phenylalanine tend to
cluster in protein interiors away from water.
Page 4
BioChem 210
Final Examination
Biochemistry •
Comprehensive Coverage of All Eight Modules
Total Questions 150 (Multiple Choice, A–D)
Sections 9 sections covering all 8 modules
Cognitive Mix 30% Recall • 50% Application • 20% Analysis
Question Style 70% Scenario-based • 20% Direct recall • 10% Calculation
Aligned Curriculum 2026–2027 Portage Learning / Geneva College CHEM 210
Examination Instructions
This comprehensive final examination consists of 150 multiple-choice questions distributed
across nine sections covering all eight modules of the CHEM 210 biochemistry curriculum.
Each question has exactly one correct answer (A, B, C, or D). Correct answers are marked
with [CORRECT] and accompanied by a comprehensive biochemistry rationale.
Section 9 (Questions 141–150) requires cross-module integrated reasoning across
metabolism, bioenergetics, and clinical scenarios.
All content is aligned with the 2026–2027 Portage Learning / Geneva College CHEM 210
curriculum standards and biochemistry competencies.
A+ Verified Comprehensive Final Examination • 150 Questions with Comprehensive Rationales
BioChem 210 Final Examination • 2026/2027 Edition
,BioChem 210 Final Exam • Biochemistry Geneva College • Portage Learning • 2026/2027
Section 1 • Module 1: Biochemistry Fundamentals, Water, pH, Buffers, Amino Acids & Protein Structure
Questions 1–25
Q1: Biochemistry is best defined as which of the following?
A. The study of cellular anatomy under a microscope
B. The study of the chemical basis of life [CORRECT]
C. The study of organic reaction mechanisms only
D. The study of physical forces in biological systems
Correct Answer: B
Rationale: Biochemistry is the study of the chemical substances and reactions that occur in living organisms, encompassing
structure, function, and metabolism of biomolecules. It bridges biology and chemistry by explaining life processes in
molecular terms. The other options either describe other disciplines (anatomy, organic chemistry, biophysics) or are too
narrow.
Q2: Which set of elements is collectively referred to by the acronym CHONPS in biochemistry?
A. Calcium, Hydrogen, Oxygen, Nickel, Phosphorus, Sulfur
B. Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur [CORRECT]
C. Carbon, Helium, Oxygen, Nitrogen, Potassium, Sodium
D. Chlorine, Hydrogen, Oxygen, Nitrogen, Phosphorus, Silicon
Correct Answer: B
Rationale: CHONPS stands for Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, and Sulfur—the six elements that
constitute the vast majority of biological molecules. Carbon forms the backbone of organic compounds, N is essential for
amino acids and nucleotides, P for nucleic acids and ATP, and S for cysteine/methionine. The other options include
non-biological or incorrect elements.
Q3: A solution has a hydrogen ion concentration of 1 × 10 ⁴ M. What is the pH of this solution?
A. pH 4 [CORRECT]
B. pH 10
C. pH 0.0001
D. pH 14
Correct Answer: A
Rationale: By definition, pH = −log[H ]. Substituting [H ] = 1 × 10 ⁴ M gives pH = −log(10 ⁴) = 4. This solution is
moderately acidic, well below physiological pH (~7.4). The pH scale is logarithmic, so each unit represents a tenfold change
in hydrogen ion concentration.
Q4: Normal human blood is maintained at a pH of approximately 7.4. A patient with metabolic acidosis has a blood
pH of 7.1. How does the hydrogen ion concentration in this patient compare to normal?
A. It is half as high
B. It is twice as high [CORRECT]
C. It is 0.3 times as high
D. There is no change in [H ]
Page 2
,BioChem 210 Final Exam • Biochemistry Geneva College • Portage Learning • 2026/2027
Correct Answer: B
Rationale: Because the pH scale is logarithmic (base 10), a decrease of 0.3 pH units corresponds to approximately a twofold
increase in [H ]. Going from pH 7.4 to 7.1 is a 0.3-unit decrease, so [H ] roughly doubles. This is why even small pH
changes are clinically significant: they reflect substantial changes in hydrogen ion concentration.
Q5: The Henderson-Hasselbalch equation relates pH, pKa, and the ratio of base to acid forms of a buffer. Which of
the following is the correct form of this equation?
A. pH = pKa + log([HA]/[A ])
B. pH = pKa + log([A ]/[HA]) [CORRECT]
C. pH = pKa − log([A ]/[HA])
D. pH = pKa × log([A ]/[HA])
Correct Answer: B
Rationale: The Henderson-Hasselbalch equation is pH = pKa + log([A ]/[HA]), where [A ] is the deprotonated (base)
form and [HA] is the protonated (acid) form. When [A ] = [HA], the log term equals zero and pH = pKa, the point of
maximum buffering capacity. Reversing the ratio or using subtraction would give incorrect pH predictions.
Q6: The bicarbonate buffer system is the primary buffer in human blood. Which sequence correctly represents the
components of this buffer system?
A. CO₂ + H₂O H₂CO₃ H + HCO₃ [CORRECT]
B. N₂ + H₂O NH₃ NH₄ + OH
C. O₂ + H₂O H₂O₂ H + HO₂
D. CO₂ + N₂ HCN H + CN
Correct Answer: A
Rationale: In the bicarbonate buffer system, CO₂ produced by cellular metabolism reacts with water to form carbonic acid
(H₂CO₃), which dissociates into H and bicarbonate (HCO₃ ). This system is especially effective because its acid component
(CO₂) is regulated by respiration and its base component (HCO₃ ) by the kidneys, providing powerful physiological control
of blood pH.
Q7: Which statement best defines pKa for a weak acid?
A. The pH at which the acid is fully protonated
B. The pH at which half of the acid molecules are protonated and half are deprotonated [CORRECT]
C. The pH at which the acid is fully deprotonated
D. The concentration of acid in solution
Correct Answer: B
Rationale: pKa is the pH at which a weak acid is 50% dissociated, meaning [HA] = [A ]. At this point, the
Henderson-Hasselbalch equation reduces to pH = pKa. pKa is an intrinsic property of a weak acid (independent of
concentration) that quantifies its tendency to donate a proton: lower pKa values indicate stronger acids.
Q8: A biochemist is preparing a buffer and needs it to be most effective at pH 6.5. The pKa values of several weak
acids are listed. Which acid would make the best buffer component?
A. Acid with pKa = 4.2
B. Acid with pKa = 5.4
C. Acid with pKa = 6.3 [CORRECT]
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, BioChem 210 Final Exam • Biochemistry Geneva College • Portage Learning • 2026/2027
D. Acid with pKa = 8.5
Correct Answer: C
Rationale: Buffers function most effectively within ±1 pH unit of their pKa, where both protonated and deprotonated forms
are present in appreciable concentrations. For a target pH of 6.5, an acid with pKa = 6.3 is ideal because the desired pH falls
well within the buffering range (5.3–7.3). The other options fall outside this optimal range and would provide little buffering
capacity at pH 6.5.
Q9: The general structure of an α-amino acid consists of a central α-carbon bonded to four groups. Which
combination correctly identifies these four substituents?
A. An amino group, a carboxyl group, a hydroxyl group, and an R-group
B. An amino group, a carboxyl group, a hydrogen atom, and an R-group [CORRECT]
C. An amino group, two carboxyl groups, and an R-group
D. Two amino groups, a hydrogen atom, and an R-group
Correct Answer: B
Rationale: All 20 standard α-amino acids share a common structure: the α-carbon is bonded to an amino group (−NH₃ at
physiological pH), a carboxyl group (−COO at physiological pH), a hydrogen atom, and a variable R-group (side chain).
The R-group is what distinguishes one amino acid from another and determines its chemical properties.
Q10: At physiological pH (~7.4), the amino group and carboxyl group of a free amino acid exist predominantly in
which ionic forms?
A. −NH₂ and −COOH
B. −NH₃ and −COO [CORRECT]
C. −NH₂ and −COO
D. −NH₃ and −COOH
Correct Answer: B
Rationale: At physiological pH, amino acids exist as zwitterions: the amino group is protonated (−NH₃ , pKa ~9–10) and the
carboxyl group is deprotonated (−COO , pKa ~2). This gives the amino acid a net charge of zero (for uncharged side
chains) but with both positive and negative charges present. The zwitterionic form is responsible for the high melting point
and crystalline nature of amino acids.
Q11: Which of the following amino acids is classified as nonpolar (hydrophobic)?
A. Serine
B. Lysine
C. Leucine [CORRECT]
D. Aspartate
Correct Answer: C
Rationale: Leucine has an isobutyl side chain that is purely hydrocarbon, making it strongly nonpolar and hydrophobic.
Serine has a hydroxyl group (polar uncharged), lysine has a positively charged amino group (basic), and aspartate has a
negatively charged carboxylate (acidic). Nonpolar amino acids such as leucine, valine, isoleucine, and phenylalanine tend to
cluster in protein interiors away from water.
Page 4
