BIOD 101 Module 1–6 & Final
Exam – 2026/2027 | Portage
Learning | Complete Verified
Q&As + Review Guide
BIOD 101 Module 1–6 & Final Exam – 2026/2027 | Portage Learning | Complete Verified Q&As +
Review Guide
Examination Overview
This 200-question multiple-choice examination covers the full scope of BIOD 101 Essential Biology I
with Lab, spanning Modules 1–6 and cumulative final exam content. The assessment is designed for
students preparing for Portage Learning’s BIOD 101 course and addresses foundational biology
concepts including biological chemistry, cell structure and function, membrane transport,
metabolism and cellular respiration, cell division and genetics, cellular signaling, and microbiology
and immunity. Questions emphasize application, analysis, and critical thinking rather than rote
recall, with realistic scenarios and data interpretation tasks distributed throughout.
Table of Contents
• Section I: Biological Chemistry and Macromolecules (Q1–Q40)
• Section II: Cell Structure, Function, and Membrane Transport (Q41–Q80)
• Section III: Cellular Metabolism and Respiration (Q81–Q120)
• Section IV: Cell Division, Genetics, and Inheritance (Q121–Q160)
• Section V: Cell Signaling, Apoptosis, and Microbiology/Immunity (Q161–Q200)
SECTION I: BIOLOGICAL CHEMISTRY AND MACROMOLECULES (Q1–Q40)
Q1. Which of the following is the primary function of carbohydrates in living organisms?
A. Catalyzing metabolic reactions
B. Storing genetic information
pg. 1
,C. Serving as the primary source of fuel
D. Forming the structural framework of cell membranes
Correct Answer: C. Serving as the primary source of fuel
Rationale: Carbohydrates are the primary source of fuel for organisms, composed of carbon,
hydrogen, and oxygen in characteristic ratios. Proteins function as enzymes and structural
molecules, nucleic acids store genetic information, and phospholipids form membrane bilayers.
Q2. A phospholipid molecule is best described as having which structural arrangement?
A. Two polar heads and one nonpolar tail
B. One polar head and two nonpolar tails
C. Two nonpolar heads and one polar tail
D. One nonpolar head and one polar tail
Correct Answer: B. One polar head and two nonpolar tails
Rationale: A phospholipid consists of a polar (hydrophilic) head group containing a charged
phosphate and typically a nitrogen-containing group, joined to two nonpolar (hydrophobic)
hydrocarbon tails derived from fatty acids. This amphipathic nature drives membrane bilayer
formation.
Q3. Which of the following statements accurately describes why lipids are insoluble in water?
A. They contain many polar covalent bonds
B. They are primarily composed of nonpolar hydrocarbon chains
C. They contain ionic bonds that repel water
D. They are too large to dissolve in water
Correct Answer: B. They are primarily composed of nonpolar hydrocarbon chains
Rationale: Water is polar, and the principle “like dissolves like” means polar solvents dissolve polar
or ionic solutes. Lipids are made mostly of nonpolar hydrocarbon chains, so they do not interact
favorably with water.
Q4. A nucleotide consists of which three components?
A. Amino acid, carboxyl group, R group
B. Phosphate group, 5-carbon sugar, nitrogenous base
C. Glycerol, fatty acid, phosphate group
D. Monosaccharide, disaccharide, polysaccharide
Correct Answer: B. Phosphate group, 5-carbon sugar, nitrogenous base
Rationale: Nucleotides, the monomers of nucleic acids, are composed of a phosphate group, a 5-
carbon sugar (deoxyribose in DNA, ribose in RNA), and a nitrogenous base. This is a foundational
definition tested repeatedly.
Q5. Which nitrogenous base is found in RNA but NOT in DNA?
A. Thymine
B. Uracil
C. Guanine
D. Adenine
pg. 2
,Correct Answer: B. Uracil
Rationale: RNA contains uracil instead of thymine. Both DNA and RNA contain adenine, guanine, and
cytosine, but DNA uses thymine while RNA uses uracil.
Q6. The “uprights” of the DNA coiled ladder model are formed by which component?
A. Nitrogenous base pairs
B. Hydrogen bonds between bases
C. Sugar-phosphate backbone
D. Phosphodiester bonds between bases
Correct Answer: C. Sugar-phosphate backbone
Rationale: The uprights of the DNA ladder are formed by alternating sugar (deoxyribose) and
phosphate groups. The rungs are formed by hydrogen-bonded base pairs (A-T and G-C).
Q7. A protein’s function is directly determined by which property?
A. Its molecular weight
B. Its amino acid sequence only
C. Its shape
D. Its charge at physiological pH
Correct Answer: C. Its shape
Rationale: The shape of a protein directly determines its function. The amino acid sequence dictates
folding, but it is the final three-dimensional conformation that enables function. Denaturation
destroys function by altering shape.
Q8. Which of the following describes the correct relationship between a polymer and its monomer
for proteins?
A. Protein → nucleotide
B. Protein → amino acid
C. Protein → monosaccharide
D. Protein → fatty acid
Correct Answer: B. Protein → amino acid
Rationale: Proteins are polymers composed of amino acid monomers linked by peptide bonds.
Nucleic acids are polymers of nucleotides, carbohydrates are polymers of monosaccharides, and
lipids are not true polymers.
Q9. An enzyme catalyzes a reaction by which mechanism?
A. Increasing the activation energy
B. Lowering the activation energy
C. Changing the equilibrium constant
D. Consuming the substrate permanently
Correct Answer: B. Lowering the activation energy
pg. 3
, Rationale: Enzymes accelerate reactions by lowering the activation energy barrier. They are not
consumed in the reaction and do not alter the equilibrium position—they only speed the approach
to equilibrium.
Q10. In competitive inhibition, how does the inhibitor affect enzyme activity?
A. It binds to the allosteric site and changes enzyme shape
B. It competes with substrate for the active site
C. It permanently denatures the enzyme
D. It increases the Vmax of the reaction
Correct Answer: B. It competes with substrate for the active site
Rationale: Competitive inhibitors bind reversibly to the active site, competing directly with
substrate. This can be overcome by increasing substrate concentration. Noncompetitive inhibitors
bind elsewhere (allosteric site).
Q11. Which type of bond holds the two strands of DNA together?
A. Covalent bonds between bases
B. Hydrogen bonds between complementary bases
C. Ionic bonds between sugar-phosphate backbones
D. Peptide bonds between nucleotides
Correct Answer: B. Hydrogen bonds between complementary bases
Rationale: The two DNA strands are held together by hydrogen bonds between complementary base
pairs—two hydrogen bonds for A-T and three for G-C. Covalent phosphodiester bonds hold
nucleotides together within a strand.
Q12. Which of the following is NOT one of the four major classes of biomacromolecules?
A. Proteins
B. Nucleic acids
C. Vitamins
D. Carbohydrates
Correct Answer: C. Vitamins
Rationale: The four major classes of biomacromolecules are carbohydrates, lipids, proteins, and
nucleic acids. Vitamins are micronutrients and are not classified as macromolecules.
Q13. A solution with a pH of 3 is how many times more acidic than a solution with a pH of 6?
A. 3 times
B. 30 times
C. 100 times
D. 1000 times
Correct Answer: D. 1000 times
Rationale: The pH scale is logarithmic. Each pH unit represents a 10-fold change in hydrogen ion
concentration. A difference of 3 pH units equals 10^3 = 1000 times difference in acidity.
Q14. Which property of water allows it to regulate temperature effectively in biological systems?
pg. 4
Exam – 2026/2027 | Portage
Learning | Complete Verified
Q&As + Review Guide
BIOD 101 Module 1–6 & Final Exam – 2026/2027 | Portage Learning | Complete Verified Q&As +
Review Guide
Examination Overview
This 200-question multiple-choice examination covers the full scope of BIOD 101 Essential Biology I
with Lab, spanning Modules 1–6 and cumulative final exam content. The assessment is designed for
students preparing for Portage Learning’s BIOD 101 course and addresses foundational biology
concepts including biological chemistry, cell structure and function, membrane transport,
metabolism and cellular respiration, cell division and genetics, cellular signaling, and microbiology
and immunity. Questions emphasize application, analysis, and critical thinking rather than rote
recall, with realistic scenarios and data interpretation tasks distributed throughout.
Table of Contents
• Section I: Biological Chemistry and Macromolecules (Q1–Q40)
• Section II: Cell Structure, Function, and Membrane Transport (Q41–Q80)
• Section III: Cellular Metabolism and Respiration (Q81–Q120)
• Section IV: Cell Division, Genetics, and Inheritance (Q121–Q160)
• Section V: Cell Signaling, Apoptosis, and Microbiology/Immunity (Q161–Q200)
SECTION I: BIOLOGICAL CHEMISTRY AND MACROMOLECULES (Q1–Q40)
Q1. Which of the following is the primary function of carbohydrates in living organisms?
A. Catalyzing metabolic reactions
B. Storing genetic information
pg. 1
,C. Serving as the primary source of fuel
D. Forming the structural framework of cell membranes
Correct Answer: C. Serving as the primary source of fuel
Rationale: Carbohydrates are the primary source of fuel for organisms, composed of carbon,
hydrogen, and oxygen in characteristic ratios. Proteins function as enzymes and structural
molecules, nucleic acids store genetic information, and phospholipids form membrane bilayers.
Q2. A phospholipid molecule is best described as having which structural arrangement?
A. Two polar heads and one nonpolar tail
B. One polar head and two nonpolar tails
C. Two nonpolar heads and one polar tail
D. One nonpolar head and one polar tail
Correct Answer: B. One polar head and two nonpolar tails
Rationale: A phospholipid consists of a polar (hydrophilic) head group containing a charged
phosphate and typically a nitrogen-containing group, joined to two nonpolar (hydrophobic)
hydrocarbon tails derived from fatty acids. This amphipathic nature drives membrane bilayer
formation.
Q3. Which of the following statements accurately describes why lipids are insoluble in water?
A. They contain many polar covalent bonds
B. They are primarily composed of nonpolar hydrocarbon chains
C. They contain ionic bonds that repel water
D. They are too large to dissolve in water
Correct Answer: B. They are primarily composed of nonpolar hydrocarbon chains
Rationale: Water is polar, and the principle “like dissolves like” means polar solvents dissolve polar
or ionic solutes. Lipids are made mostly of nonpolar hydrocarbon chains, so they do not interact
favorably with water.
Q4. A nucleotide consists of which three components?
A. Amino acid, carboxyl group, R group
B. Phosphate group, 5-carbon sugar, nitrogenous base
C. Glycerol, fatty acid, phosphate group
D. Monosaccharide, disaccharide, polysaccharide
Correct Answer: B. Phosphate group, 5-carbon sugar, nitrogenous base
Rationale: Nucleotides, the monomers of nucleic acids, are composed of a phosphate group, a 5-
carbon sugar (deoxyribose in DNA, ribose in RNA), and a nitrogenous base. This is a foundational
definition tested repeatedly.
Q5. Which nitrogenous base is found in RNA but NOT in DNA?
A. Thymine
B. Uracil
C. Guanine
D. Adenine
pg. 2
,Correct Answer: B. Uracil
Rationale: RNA contains uracil instead of thymine. Both DNA and RNA contain adenine, guanine, and
cytosine, but DNA uses thymine while RNA uses uracil.
Q6. The “uprights” of the DNA coiled ladder model are formed by which component?
A. Nitrogenous base pairs
B. Hydrogen bonds between bases
C. Sugar-phosphate backbone
D. Phosphodiester bonds between bases
Correct Answer: C. Sugar-phosphate backbone
Rationale: The uprights of the DNA ladder are formed by alternating sugar (deoxyribose) and
phosphate groups. The rungs are formed by hydrogen-bonded base pairs (A-T and G-C).
Q7. A protein’s function is directly determined by which property?
A. Its molecular weight
B. Its amino acid sequence only
C. Its shape
D. Its charge at physiological pH
Correct Answer: C. Its shape
Rationale: The shape of a protein directly determines its function. The amino acid sequence dictates
folding, but it is the final three-dimensional conformation that enables function. Denaturation
destroys function by altering shape.
Q8. Which of the following describes the correct relationship between a polymer and its monomer
for proteins?
A. Protein → nucleotide
B. Protein → amino acid
C. Protein → monosaccharide
D. Protein → fatty acid
Correct Answer: B. Protein → amino acid
Rationale: Proteins are polymers composed of amino acid monomers linked by peptide bonds.
Nucleic acids are polymers of nucleotides, carbohydrates are polymers of monosaccharides, and
lipids are not true polymers.
Q9. An enzyme catalyzes a reaction by which mechanism?
A. Increasing the activation energy
B. Lowering the activation energy
C. Changing the equilibrium constant
D. Consuming the substrate permanently
Correct Answer: B. Lowering the activation energy
pg. 3
, Rationale: Enzymes accelerate reactions by lowering the activation energy barrier. They are not
consumed in the reaction and do not alter the equilibrium position—they only speed the approach
to equilibrium.
Q10. In competitive inhibition, how does the inhibitor affect enzyme activity?
A. It binds to the allosteric site and changes enzyme shape
B. It competes with substrate for the active site
C. It permanently denatures the enzyme
D. It increases the Vmax of the reaction
Correct Answer: B. It competes with substrate for the active site
Rationale: Competitive inhibitors bind reversibly to the active site, competing directly with
substrate. This can be overcome by increasing substrate concentration. Noncompetitive inhibitors
bind elsewhere (allosteric site).
Q11. Which type of bond holds the two strands of DNA together?
A. Covalent bonds between bases
B. Hydrogen bonds between complementary bases
C. Ionic bonds between sugar-phosphate backbones
D. Peptide bonds between nucleotides
Correct Answer: B. Hydrogen bonds between complementary bases
Rationale: The two DNA strands are held together by hydrogen bonds between complementary base
pairs—two hydrogen bonds for A-T and three for G-C. Covalent phosphodiester bonds hold
nucleotides together within a strand.
Q12. Which of the following is NOT one of the four major classes of biomacromolecules?
A. Proteins
B. Nucleic acids
C. Vitamins
D. Carbohydrates
Correct Answer: C. Vitamins
Rationale: The four major classes of biomacromolecules are carbohydrates, lipids, proteins, and
nucleic acids. Vitamins are micronutrients and are not classified as macromolecules.
Q13. A solution with a pH of 3 is how many times more acidic than a solution with a pH of 6?
A. 3 times
B. 30 times
C. 100 times
D. 1000 times
Correct Answer: D. 1000 times
Rationale: The pH scale is logarithmic. Each pH unit represents a 10-fold change in hydrogen ion
concentration. A difference of 3 pH units equals 10^3 = 1000 times difference in acidity.
Q14. Which property of water allows it to regulate temperature effectively in biological systems?
pg. 4
