CHEM 210
OBJECTIVE ASSESSMENT - EXAM
CHEM 210 Biochemistry Module 1
to 8 Exams' & Final Exam
(2026/2027) Portage Learning
Questions and Verified Answers,
100% Guaranteed Pass || Complete
A+ Guide
Portage Learning | Biochemistry Certification Exam
150 100% 2026/2027
QUESTIONS VERIFIED ANSWERS EDITION
TOPICS COVERED
• Amino Acid Chemistry & Protein Structure • Enzyme Kinetics & Inhibition Mechanisms
• Glycolysis & Gluconeogenesis Regulation • Citric Acid Cycle & Oxidative Phosphorylation
• DNA Replication, Transcription & Repair • Gene Expression & Metabolic Regulation
COVER PAGE - 1
,SECTION 1 | Module 1-2: Biomolecules & Enzyme Kinetics | Q1-Q33 | CHEM 210 Biochemistry 2026/2027
Q1 Question 1 of 150
A 34-year-old patient with a rare genetic disorder presents with elevated levels of phenylalanine in
the blood. Laboratory analysis reveals a deficiency in the enzyme phenylalanine hydroxylase. Which
amino acid classification best describes phenylalanine?
A. Nonpolar aromatic
B. Polar uncharged
C. Positively charged
D. Negatively charged
Correct Answer: A
Rationale:
Phenylalanine is classified as a nonpolar aromatic amino acid due to its benzyl side chain that is hydrophobic and contains
an aromatic ring. It is not polar, positively charged (basic), or negatively charged (acidic).
Q2 Question 2 of 150
During a biochemistry lab experiment, a student measures the optical rotation of a freshly prepared
solution of L-alanine. Which of the following correctly describes the stereochemical configuration of
all proteinogenic amino acids found in human proteins?
A. All are L-amino acids except glycine
B. All are D-amino acids
C. A mixture of L and D forms
D. All are racemic mixtures
Correct Answer: A
Rationale:
All proteinogenic amino acids in human proteins are L-amino acids. Glycine is achiral and therefore has no D or L
configuration, making it the only exception among the 20 standard amino acids.
Q3 Question 3 of 150
A researcher is studying protein folding using circular dichroism spectroscopy. The spectrum shows
strong negative bands at 222 nm and 208 nm. Which secondary structure is predominantly present
in this protein sample?
A. Alpha helix
B. Beta sheet
C. Beta turn
D. Random coil
Correct Answer: A
CHEM 210 Biochemistry - 2026/2027 | Passing Score: 80%
Rationale:
Alpha helices characteristically produce negative circular dichroism bands at 222 nm and 208 nm, along with a positive
,SECTION 1 | Module 1-2: Biomolecules & Enzyme Kinetics | Q1-Q33 | CHEM 210 Biochemistry 2026/2027
Q4 Question 4 of 150
In a clinical assay, a patient's hemoglobin sample shows increased oxygen affinity compared to
normal hemoglobin. Which allosteric effector is most likely decreased in this patient's red blood cells?
A. 2,3-Bisphosphoglycerate
B. Carbon dioxide
C. Hydrogen ions
D. Chloride ions
Correct Answer: A
Rationale:
2,3-Bisphosphoglycerate (2,3-BPG) binds to the central cavity of deoxyhemoglobin and stabilizes the T-state, decreasing
oxygen affinity. Lower 2,3-BPG levels would increase oxygen affinity, shifting the curve left.
Q5 Question 5 of 150
A biochemistry student is analyzing the primary structure of a newly discovered protein. The
sequence contains 200 amino acid residues. How many peptide bonds are present in this linear
polypeptide chain?
A. 199
B. 200
C. 201
D. 198
Correct Answer: A
Rationale:
In a linear polypeptide chain, the number of peptide bonds equals the number of amino acid residues minus one. For 200
residues, there are 199 peptide bonds formed during translation.
Q6 Question 6 of 150
During an enzyme kinetics experiment, the Vmax of an enzyme-catalyzed reaction is determined to
be 120 micromol/min. When the substrate concentration is equal to the Km value, what is the
reaction velocity?
A. 60 micromol/min
B. 120 micromol/min
C. 30 micromol/min
D. 90 micromol/min
Correct Answer: A
Rationale:
CHEM 210 Biochemistry - 2026/2027 | Passing Score: 80%
According to the Michaelis-Menten equation, when substrate concentration equals Km, the reaction velocity is exactly half
of Vmax. Therefore, 120/2 = 60 micromol/min.
, SECTION 1 | Module 1-2: Biomolecules & Enzyme Kinetics | Q1-Q33 | CHEM 210 Biochemistry 2026/2027
Q7 Question 7 of 150
A pharmaceutical researcher is testing a new drug that acts as a competitive inhibitor of
acetylcholinesterase. Which kinetic parameter will be altered by this inhibitor, and how?
A. Km increases; Vmax unchanged
B. Km decreases; Vmax unchanged
C. Km unchanged; Vmax decreases
D. Both Km and Vmax decrease
Correct Answer: A
Rationale:
Competitive inhibitors increase the apparent Km because more substrate is needed to reach half-maximal velocity, but
Vmax remains unchanged since sufficient substrate can overcome the inhibition.
Q8 Question 8 of 150
In a study of enzyme regulation, an investigator observes that the activity of phosphofructokinase-1
decreases when ATP levels are high. What type of enzyme regulation is being demonstrated?
A. Allosteric inhibition
B. Covalent modification
C. Competitive inhibition
D. Proteolytic cleavage
Correct Answer: A
Rationale:
ATP acts as an allosteric inhibitor of phosphofructokinase-1. High ATP levels bind to the allosteric site and decrease the
enzyme's affinity for fructose-6-phosphate, slowing glycolysis when energy is abundant.
Q9 Question 9 of 150
A patient presents with symptoms of celiac disease. Laboratory analysis reveals antibodies against a
specific enzyme in the small intestine. Which enzyme is responsible for the final digestion of peptides
into free amino acids in the brush border?
A. Aminopeptidase
B. Pepsin
C. Trypsin
D. Chymotrypsin
Correct Answer: A
Rationale:
Aminopeptidase is a brush border enzyme that cleaves amino acids from the N-terminus of peptides, completing protein
CHEM 210 Biochemistry - 2026/2027 | Passing Score: 80%
digestion. Pepsin, trypsin, and chymotrypsin are endopeptidases that produce smaller peptides, not free amino acids.
OBJECTIVE ASSESSMENT - EXAM
CHEM 210 Biochemistry Module 1
to 8 Exams' & Final Exam
(2026/2027) Portage Learning
Questions and Verified Answers,
100% Guaranteed Pass || Complete
A+ Guide
Portage Learning | Biochemistry Certification Exam
150 100% 2026/2027
QUESTIONS VERIFIED ANSWERS EDITION
TOPICS COVERED
• Amino Acid Chemistry & Protein Structure • Enzyme Kinetics & Inhibition Mechanisms
• Glycolysis & Gluconeogenesis Regulation • Citric Acid Cycle & Oxidative Phosphorylation
• DNA Replication, Transcription & Repair • Gene Expression & Metabolic Regulation
COVER PAGE - 1
,SECTION 1 | Module 1-2: Biomolecules & Enzyme Kinetics | Q1-Q33 | CHEM 210 Biochemistry 2026/2027
Q1 Question 1 of 150
A 34-year-old patient with a rare genetic disorder presents with elevated levels of phenylalanine in
the blood. Laboratory analysis reveals a deficiency in the enzyme phenylalanine hydroxylase. Which
amino acid classification best describes phenylalanine?
A. Nonpolar aromatic
B. Polar uncharged
C. Positively charged
D. Negatively charged
Correct Answer: A
Rationale:
Phenylalanine is classified as a nonpolar aromatic amino acid due to its benzyl side chain that is hydrophobic and contains
an aromatic ring. It is not polar, positively charged (basic), or negatively charged (acidic).
Q2 Question 2 of 150
During a biochemistry lab experiment, a student measures the optical rotation of a freshly prepared
solution of L-alanine. Which of the following correctly describes the stereochemical configuration of
all proteinogenic amino acids found in human proteins?
A. All are L-amino acids except glycine
B. All are D-amino acids
C. A mixture of L and D forms
D. All are racemic mixtures
Correct Answer: A
Rationale:
All proteinogenic amino acids in human proteins are L-amino acids. Glycine is achiral and therefore has no D or L
configuration, making it the only exception among the 20 standard amino acids.
Q3 Question 3 of 150
A researcher is studying protein folding using circular dichroism spectroscopy. The spectrum shows
strong negative bands at 222 nm and 208 nm. Which secondary structure is predominantly present
in this protein sample?
A. Alpha helix
B. Beta sheet
C. Beta turn
D. Random coil
Correct Answer: A
CHEM 210 Biochemistry - 2026/2027 | Passing Score: 80%
Rationale:
Alpha helices characteristically produce negative circular dichroism bands at 222 nm and 208 nm, along with a positive
,SECTION 1 | Module 1-2: Biomolecules & Enzyme Kinetics | Q1-Q33 | CHEM 210 Biochemistry 2026/2027
Q4 Question 4 of 150
In a clinical assay, a patient's hemoglobin sample shows increased oxygen affinity compared to
normal hemoglobin. Which allosteric effector is most likely decreased in this patient's red blood cells?
A. 2,3-Bisphosphoglycerate
B. Carbon dioxide
C. Hydrogen ions
D. Chloride ions
Correct Answer: A
Rationale:
2,3-Bisphosphoglycerate (2,3-BPG) binds to the central cavity of deoxyhemoglobin and stabilizes the T-state, decreasing
oxygen affinity. Lower 2,3-BPG levels would increase oxygen affinity, shifting the curve left.
Q5 Question 5 of 150
A biochemistry student is analyzing the primary structure of a newly discovered protein. The
sequence contains 200 amino acid residues. How many peptide bonds are present in this linear
polypeptide chain?
A. 199
B. 200
C. 201
D. 198
Correct Answer: A
Rationale:
In a linear polypeptide chain, the number of peptide bonds equals the number of amino acid residues minus one. For 200
residues, there are 199 peptide bonds formed during translation.
Q6 Question 6 of 150
During an enzyme kinetics experiment, the Vmax of an enzyme-catalyzed reaction is determined to
be 120 micromol/min. When the substrate concentration is equal to the Km value, what is the
reaction velocity?
A. 60 micromol/min
B. 120 micromol/min
C. 30 micromol/min
D. 90 micromol/min
Correct Answer: A
Rationale:
CHEM 210 Biochemistry - 2026/2027 | Passing Score: 80%
According to the Michaelis-Menten equation, when substrate concentration equals Km, the reaction velocity is exactly half
of Vmax. Therefore, 120/2 = 60 micromol/min.
, SECTION 1 | Module 1-2: Biomolecules & Enzyme Kinetics | Q1-Q33 | CHEM 210 Biochemistry 2026/2027
Q7 Question 7 of 150
A pharmaceutical researcher is testing a new drug that acts as a competitive inhibitor of
acetylcholinesterase. Which kinetic parameter will be altered by this inhibitor, and how?
A. Km increases; Vmax unchanged
B. Km decreases; Vmax unchanged
C. Km unchanged; Vmax decreases
D. Both Km and Vmax decrease
Correct Answer: A
Rationale:
Competitive inhibitors increase the apparent Km because more substrate is needed to reach half-maximal velocity, but
Vmax remains unchanged since sufficient substrate can overcome the inhibition.
Q8 Question 8 of 150
In a study of enzyme regulation, an investigator observes that the activity of phosphofructokinase-1
decreases when ATP levels are high. What type of enzyme regulation is being demonstrated?
A. Allosteric inhibition
B. Covalent modification
C. Competitive inhibition
D. Proteolytic cleavage
Correct Answer: A
Rationale:
ATP acts as an allosteric inhibitor of phosphofructokinase-1. High ATP levels bind to the allosteric site and decrease the
enzyme's affinity for fructose-6-phosphate, slowing glycolysis when energy is abundant.
Q9 Question 9 of 150
A patient presents with symptoms of celiac disease. Laboratory analysis reveals antibodies against a
specific enzyme in the small intestine. Which enzyme is responsible for the final digestion of peptides
into free amino acids in the brush border?
A. Aminopeptidase
B. Pepsin
C. Trypsin
D. Chymotrypsin
Correct Answer: A
Rationale:
Aminopeptidase is a brush border enzyme that cleaves amino acids from the N-terminus of peptides, completing protein
CHEM 210 Biochemistry - 2026/2027 | Passing Score: 80%
digestion. Pepsin, trypsin, and chymotrypsin are endopeptidases that produce smaller peptides, not free amino acids.
