, BIOL 101 FINAL EXAM
Essential Biology I w/Lab
Portage Learning
100-Question Cumulative Practice Examination
2026/2027 Edition
Directions: Select the best answer for each question. This original cumulative study assessment covers Modules
1-6: biological chemistry and cell biology; properties of life and classification; cellular respiration and enzymes;
heredity, inheritance, and the cell cycle; cell signaling; and microbiology and immune responses.
BIOL 101 final Module Exam | Essential Biology I w/Lab | Portage Learning
| Q & A | 2026/2027 Edition (PDF)
1. Which interaction is responsible for water molecules attracting one another?
A) Ionic bonding between water molecules
B) Peptide bonding
C) Hydrogen bonding
D) Disulfide bonding
Correct Answer: C) Hydrogen bonding
Rationale: Water is polar, so the partially positive hydrogen of one molecule is attracted to the partially negative
oxygen of another. These intermolecular hydrogen bonds explain cohesion, surface tension, and many solvent
properties of water.
2. A solution with pH 3 has how many times more hydrogen ions than a solution with pH 5?
A) 10 times
B) 2 times
C) 1000 times
D) 100 times
Correct Answer: D) 100 times
Rationale: The pH scale is logarithmic. A difference of two pH units corresponds to a 10^2, or 100-fold, difference
in hydrogen-ion concentration.
3. Which macromolecule is composed of amino-acid monomers?
A) Protein
B) Triglyceride
C) Nucleic acid
D) Carbohydrate
Correct Answer: A) Protein
Rationale: Proteins are polymers of amino acids linked by peptide bonds. Carbohydrates are built from sugars,
nucleic acids from nucleotides, and triglycerides from glycerol plus fatty acids.
BIOL 101 Final Practice Examination | 2026/2027 Edition Page 1
, 4. Which feature most directly distinguishes a phospholipid from a triglyceride?
A) A phosphate-containing polar head
B) A nitrogenous base
C) Three amino-acid chains
D) A ribose sugar
Correct Answer: A) A phosphate-containing polar head
Rationale: Phospholipids contain a phosphate-containing polar head and hydrophobic fatty-acid tails, allowing
bilayer formation. Triglycerides instead contain glycerol esterified to three fatty acids and are primarily energy-
storage molecules.
5. An enzyme accelerates a biochemical reaction primarily by:
A) Lowering activation energy
B) Changing the reaction equilibrium
C) Being consumed as a reactant
D) Raising the reaction's free-energy change
Correct Answer: A) Lowering activation energy
Rationale: Enzymes provide a lower-energy pathway to the transition state. They do not change the overall free-
energy difference or equilibrium and are regenerated after the reaction.
6. Which organelle is the principal site of ATP production during aerobic respiration?
A) Lysosome
B) Golgi apparatus
C) Mitochondrion
D) Nucleolus
Correct Answer: C) Mitochondrion
Rationale: Mitochondria contain the enzymes of the TCA cycle and oxidative phosphorylation. The Golgi modifies
and sorts proteins, lysosomes contain digestive enzymes, and the nucleolus produces ribosomal components.
7. A protein destined for secretion is most likely synthesized by ribosomes attached to the:
A) Centrosome
B) Rough endoplasmic reticulum
C) Smooth endoplasmic reticulum
D) Peroxisome
Correct Answer: B) Rough endoplasmic reticulum
Rationale: Secreted and many membrane proteins enter the rough ER during translation, then pass through the
Golgi for processing and trafficking. Smooth ER lacks bound ribosomes and specializes in lipid synthesis and
detoxification.
8. Which organelle modifies, sorts, and packages many proteins for transport?
A) Golgi apparatus
B) Nucleus
C) Mitochondrion
BIOL 101 Final Practice Examination | 2026/2027 Edition Page 2
Essential Biology I w/Lab
Portage Learning
100-Question Cumulative Practice Examination
2026/2027 Edition
Directions: Select the best answer for each question. This original cumulative study assessment covers Modules
1-6: biological chemistry and cell biology; properties of life and classification; cellular respiration and enzymes;
heredity, inheritance, and the cell cycle; cell signaling; and microbiology and immune responses.
BIOL 101 final Module Exam | Essential Biology I w/Lab | Portage Learning
| Q & A | 2026/2027 Edition (PDF)
1. Which interaction is responsible for water molecules attracting one another?
A) Ionic bonding between water molecules
B) Peptide bonding
C) Hydrogen bonding
D) Disulfide bonding
Correct Answer: C) Hydrogen bonding
Rationale: Water is polar, so the partially positive hydrogen of one molecule is attracted to the partially negative
oxygen of another. These intermolecular hydrogen bonds explain cohesion, surface tension, and many solvent
properties of water.
2. A solution with pH 3 has how many times more hydrogen ions than a solution with pH 5?
A) 10 times
B) 2 times
C) 1000 times
D) 100 times
Correct Answer: D) 100 times
Rationale: The pH scale is logarithmic. A difference of two pH units corresponds to a 10^2, or 100-fold, difference
in hydrogen-ion concentration.
3. Which macromolecule is composed of amino-acid monomers?
A) Protein
B) Triglyceride
C) Nucleic acid
D) Carbohydrate
Correct Answer: A) Protein
Rationale: Proteins are polymers of amino acids linked by peptide bonds. Carbohydrates are built from sugars,
nucleic acids from nucleotides, and triglycerides from glycerol plus fatty acids.
BIOL 101 Final Practice Examination | 2026/2027 Edition Page 1
, 4. Which feature most directly distinguishes a phospholipid from a triglyceride?
A) A phosphate-containing polar head
B) A nitrogenous base
C) Three amino-acid chains
D) A ribose sugar
Correct Answer: A) A phosphate-containing polar head
Rationale: Phospholipids contain a phosphate-containing polar head and hydrophobic fatty-acid tails, allowing
bilayer formation. Triglycerides instead contain glycerol esterified to three fatty acids and are primarily energy-
storage molecules.
5. An enzyme accelerates a biochemical reaction primarily by:
A) Lowering activation energy
B) Changing the reaction equilibrium
C) Being consumed as a reactant
D) Raising the reaction's free-energy change
Correct Answer: A) Lowering activation energy
Rationale: Enzymes provide a lower-energy pathway to the transition state. They do not change the overall free-
energy difference or equilibrium and are regenerated after the reaction.
6. Which organelle is the principal site of ATP production during aerobic respiration?
A) Lysosome
B) Golgi apparatus
C) Mitochondrion
D) Nucleolus
Correct Answer: C) Mitochondrion
Rationale: Mitochondria contain the enzymes of the TCA cycle and oxidative phosphorylation. The Golgi modifies
and sorts proteins, lysosomes contain digestive enzymes, and the nucleolus produces ribosomal components.
7. A protein destined for secretion is most likely synthesized by ribosomes attached to the:
A) Centrosome
B) Rough endoplasmic reticulum
C) Smooth endoplasmic reticulum
D) Peroxisome
Correct Answer: B) Rough endoplasmic reticulum
Rationale: Secreted and many membrane proteins enter the rough ER during translation, then pass through the
Golgi for processing and trafficking. Smooth ER lacks bound ribosomes and specializes in lipid synthesis and
detoxification.
8. Which organelle modifies, sorts, and packages many proteins for transport?
A) Golgi apparatus
B) Nucleus
C) Mitochondrion
BIOL 101 Final Practice Examination | 2026/2027 Edition Page 2
