BIOCHEM 210 Final Exam 2026 | Questions with
Answers & Detailed Explanations | Portage Learning |
Latest Version | Guaranteed Pass
Description
Complete BIOCHEM 210 Final Exam 2026 preparation guide containing 200 multiple-choice practice
questions with verified answers and detailed explanations in italic.
This comprehensive study resource covers all essential topics from the BIOCHEM 210 Final Exam :
✅ Foundations of Biochemistry & Water Chemistry – Carbon properties, bulk elements (C, H, O, N),
pH calculations (pH = -log[H⁺]), Henderson-Hasselbalch equation, buffers, water polarity, hydrogen
bonding, non-covalent interactions, cell biology fundamentals
✅ Amino Acids & Protein Structure – 20 standard amino acids, peptide bonds,
primary/secondary/tertiary/quaternary structure, alpha-helices (i → i+4 hydrogen bonding), beta-sheets,
disulfide bonds, zwitterions, chiral carbon, enzyme-substrate interactions, competitive vs noncompetitive
inhibition, EC classification (kinases, hydrolases, transferases)
✅ Nucleic Acids & Molecular Biology – DNA (A-T, G-C), RNA (A-U), nucleotides, DNA replication
(helicase, DNA polymerase), transcription (RNA polymerase), translation, central dogma, pyrimidines vs
purines
✅ Metabolism – Glycolysis & Citric Acid Cycle – Glycolysis (2 ATP net, PFK regulation), citric acid
cycle (3 NADH, 1 FADH₂, 1 GTP), pyruvate dehydrogenase, electron transport chain (Complex I-IV, ATP
synthase), oxidative phosphorylation, FADH₂ vs NADH energy yield
✅ Lipids & Membranes – Fatty acids (saturated vs unsaturated), triacylglycerols (ester bonds),
phospholipids, cholesterol, fluid mosaic model, hydrophobic effect
✅ Metabolic Integration & Regulation – Hormones (insulin, glucagon), glycogen metabolism,
gluconeogenesis, pentose phosphate pathway, ketone bodies, urea cycle, anabolic vs catabolic pathways
✅ Signal Transduction – Second messengers (cAMP, Ca²⁺, IP₃, DAG), GPCR pathways, adenylyl
cyclase, phosphodiesterase, protein kinases (PKA, PKC), receptor tyrosine kinases, MAP kinase pathway
, ✅ Biochemical Techniques – Western blotting, Southern blotting, Northern blotting, PCR, gel
electrophoresis, Bradford assay, co-immunoprecipitation
✅ Clinical Biochemistry – Metabolic acidosis/alkalosis, respiratory acidosis/alkalosis, inborn errors of
metabolism, enzyme deficiencies
Section 1: Foundations of Biochemistry & Water Chemistry (Questions 1–25)
1. Which element is considered the "superglue of the chemical world" because it can
form long chains, rings, and stable bonds with many other atoms?
A) Hydrogen
B) Oxygen
C) Carbon
D) Nitrogen
Answer: C
Explanation: Carbon has four valence electrons, allowing it to form four stable covalent
bonds. This enables carbon to create long chains, branched structures, and ring
compounds. It also forms bonds with many other atoms including hydrogen, nitrogen, and
oxygen, making it the essential backbone of all organic molecules in biochemistry .
Hydrogen forms only one bond, oxygen typically forms two bonds, and nitrogen forms three
bonds, limiting their structural diversity.
2. What is the primary difference between organic and inorganic compounds?
, A) Organic compounds are found only in living things; inorganic compounds are not
B) Organic compounds contain carbon-hydrogen bonds; inorganic compounds typically do
not
C) Organic compounds are always larger than inorganic compounds
D) Organic compounds contain oxygen; inorganic compounds do not
Answer: B
Explanation: Organic chemistry is defined as the study of carbon-containing compounds,
specifically those with carbon-hydrogen (C–H) bonds. Inorganic compounds may contain
carbon (e.g., carbon dioxide, carbonates) but lack C–H bonds . Urea and other organic
compounds can be synthesized in the laboratory, and molecular size is not a defining
characteristic.
3. What are the four most abundant elements found in living organisms?
A) Carbon, Hydrogen, Oxygen, Nitrogen
B) Carbon, Hydrogen, Oxygen, Sodium
C) Carbon, Nitrogen, Oxygen, Phosphorus
D) Carbon, Hydrogen, Nitrogen, Sulfur
Answer: A
Explanation: These four elements make up approximately 96% of the mass of most living
organisms. They are considered "bulk elements" and form the backbone of all major
biomolecules: carbohydrates (C, H, O), proteins (C, H, O, N, S), lipids (C, H, O), and nucleic
acids (C, H, O, N, P) . Sodium is a trace element, phosphorus is important but not among
the top four, and sulfur is present in some amino acids but not among the top four.
, 4. Which property of water is MOST critical for its role as the universal biological
solvent?
A) Low heat capacity
B) High polarity and hydrogen bonding capability
C) Low surface tension
D) Non-polar character
Answer: B
Explanation: Water's high polarity (electronegativity difference between O and H) and
extensive hydrogen bonding enable dissolution of ionic and polar compounds, stabilization
of biomolecular structures, and participation in metabolic reactions. Water has high (not low)
heat capacity, high surface tension, and is polar .
5. Which statement correctly describes water's role in biological systems?
A) Water is a poor solvent for charged molecules
B) Water can make up to 85% of a living organism's mass
C) Water is considered a non-polar solvent
D) Water molecules cannot form hydrogen bonds
Answer: B
Explanation: Water is known as the "medium of life." In many organisms, water constitutes
70–85% of total mass. Its polar nature allows it to serve as an excellent solvent for ions and
polar molecules. Water's ability to form hydrogen bonds is critical for its unique properties .
Answers & Detailed Explanations | Portage Learning |
Latest Version | Guaranteed Pass
Description
Complete BIOCHEM 210 Final Exam 2026 preparation guide containing 200 multiple-choice practice
questions with verified answers and detailed explanations in italic.
This comprehensive study resource covers all essential topics from the BIOCHEM 210 Final Exam :
✅ Foundations of Biochemistry & Water Chemistry – Carbon properties, bulk elements (C, H, O, N),
pH calculations (pH = -log[H⁺]), Henderson-Hasselbalch equation, buffers, water polarity, hydrogen
bonding, non-covalent interactions, cell biology fundamentals
✅ Amino Acids & Protein Structure – 20 standard amino acids, peptide bonds,
primary/secondary/tertiary/quaternary structure, alpha-helices (i → i+4 hydrogen bonding), beta-sheets,
disulfide bonds, zwitterions, chiral carbon, enzyme-substrate interactions, competitive vs noncompetitive
inhibition, EC classification (kinases, hydrolases, transferases)
✅ Nucleic Acids & Molecular Biology – DNA (A-T, G-C), RNA (A-U), nucleotides, DNA replication
(helicase, DNA polymerase), transcription (RNA polymerase), translation, central dogma, pyrimidines vs
purines
✅ Metabolism – Glycolysis & Citric Acid Cycle – Glycolysis (2 ATP net, PFK regulation), citric acid
cycle (3 NADH, 1 FADH₂, 1 GTP), pyruvate dehydrogenase, electron transport chain (Complex I-IV, ATP
synthase), oxidative phosphorylation, FADH₂ vs NADH energy yield
✅ Lipids & Membranes – Fatty acids (saturated vs unsaturated), triacylglycerols (ester bonds),
phospholipids, cholesterol, fluid mosaic model, hydrophobic effect
✅ Metabolic Integration & Regulation – Hormones (insulin, glucagon), glycogen metabolism,
gluconeogenesis, pentose phosphate pathway, ketone bodies, urea cycle, anabolic vs catabolic pathways
✅ Signal Transduction – Second messengers (cAMP, Ca²⁺, IP₃, DAG), GPCR pathways, adenylyl
cyclase, phosphodiesterase, protein kinases (PKA, PKC), receptor tyrosine kinases, MAP kinase pathway
, ✅ Biochemical Techniques – Western blotting, Southern blotting, Northern blotting, PCR, gel
electrophoresis, Bradford assay, co-immunoprecipitation
✅ Clinical Biochemistry – Metabolic acidosis/alkalosis, respiratory acidosis/alkalosis, inborn errors of
metabolism, enzyme deficiencies
Section 1: Foundations of Biochemistry & Water Chemistry (Questions 1–25)
1. Which element is considered the "superglue of the chemical world" because it can
form long chains, rings, and stable bonds with many other atoms?
A) Hydrogen
B) Oxygen
C) Carbon
D) Nitrogen
Answer: C
Explanation: Carbon has four valence electrons, allowing it to form four stable covalent
bonds. This enables carbon to create long chains, branched structures, and ring
compounds. It also forms bonds with many other atoms including hydrogen, nitrogen, and
oxygen, making it the essential backbone of all organic molecules in biochemistry .
Hydrogen forms only one bond, oxygen typically forms two bonds, and nitrogen forms three
bonds, limiting their structural diversity.
2. What is the primary difference between organic and inorganic compounds?
, A) Organic compounds are found only in living things; inorganic compounds are not
B) Organic compounds contain carbon-hydrogen bonds; inorganic compounds typically do
not
C) Organic compounds are always larger than inorganic compounds
D) Organic compounds contain oxygen; inorganic compounds do not
Answer: B
Explanation: Organic chemistry is defined as the study of carbon-containing compounds,
specifically those with carbon-hydrogen (C–H) bonds. Inorganic compounds may contain
carbon (e.g., carbon dioxide, carbonates) but lack C–H bonds . Urea and other organic
compounds can be synthesized in the laboratory, and molecular size is not a defining
characteristic.
3. What are the four most abundant elements found in living organisms?
A) Carbon, Hydrogen, Oxygen, Nitrogen
B) Carbon, Hydrogen, Oxygen, Sodium
C) Carbon, Nitrogen, Oxygen, Phosphorus
D) Carbon, Hydrogen, Nitrogen, Sulfur
Answer: A
Explanation: These four elements make up approximately 96% of the mass of most living
organisms. They are considered "bulk elements" and form the backbone of all major
biomolecules: carbohydrates (C, H, O), proteins (C, H, O, N, S), lipids (C, H, O), and nucleic
acids (C, H, O, N, P) . Sodium is a trace element, phosphorus is important but not among
the top four, and sulfur is present in some amino acids but not among the top four.
, 4. Which property of water is MOST critical for its role as the universal biological
solvent?
A) Low heat capacity
B) High polarity and hydrogen bonding capability
C) Low surface tension
D) Non-polar character
Answer: B
Explanation: Water's high polarity (electronegativity difference between O and H) and
extensive hydrogen bonding enable dissolution of ionic and polar compounds, stabilization
of biomolecular structures, and participation in metabolic reactions. Water has high (not low)
heat capacity, high surface tension, and is polar .
5. Which statement correctly describes water's role in biological systems?
A) Water is a poor solvent for charged molecules
B) Water can make up to 85% of a living organism's mass
C) Water is considered a non-polar solvent
D) Water molecules cannot form hydrogen bonds
Answer: B
Explanation: Water is known as the "medium of life." In many organisms, water constitutes
70–85% of total mass. Its polar nature allows it to serve as an excellent solvent for ions and
polar molecules. Water's ability to form hydrogen bonds is critical for its unique properties .
