ACTUAL EXAM | 150 QUESTIONS & CORRECT ANSWERS | ALREADY GRADED
A+ | 100% VERIFIED
Washington State University Biology 106 | Cellular Biology, Genetics, Evolution, Ecology,
Energy Flow, Biological Molecules, Physiology, and Laboratory-Informed Concepts |
Expert-Verified Format & Structure | Exam-Ready
Introduction
This fully updated 2025–2026 Biology 106 Exam resource follows the exact format used for
both Version A and Version B of WSU’s actual Exam 1 and Exam 2 structures. It includes
accurate biological themes such as cellular processes, genetic mechanisms, evolutionary
patterns, and ecological interactions. All exam content created using this format is aligned with
foundational and advanced biological principles, emphasizing academic precision and
conceptual mastery.
Answer Format
All correct answers appear in bold, accompanied by clear, concise rationales explaining
underlying biological concepts, reinforcing scientific reasoning, and strengthening exam-level
comprehension.
EXAM 1 – VERSION A (Questions 1–75)
1. Which organelle is primarily responsible for the post-translational modification and
packaging of proteins?
A. Nucleus
B. Golgi apparatus
C. Ribosome
D. Lysosome
Rationale: The Golgi apparatus modifies, sorts, and packages proteins received from
the rough ER for secretion or delivery to other organelles.
2. In a hypotonic solution, a plant cell will:
A. Shrink
B. Become turgid
C. Lyse
D. Remain unchanged
Rationale: Water enters the central vacuole, creating turgor pressure against the rigid
cell wall, making the cell firm but not lysing.
3. Which of the following best describes the function of ATP in cellular metabolism?
A. DNA replication
B. Energy currency for cellular work
C. Structural support
D. Enzyme inhibition
, Rationale: ATP hydrolysis releases energy used to drive endergonic reactions like
muscle contraction, active transport, and biosynthesis.
4. The movement of water across a semipermeable membrane is called:
A. Diffusion
B. Osmosis
C. Active transport
D. Facilitated diffusion
Rationale: Osmosis is the diffusion of water from a region of lower solute
concentration to higher solute concentration.
5. During which phase of mitosis do sister chromatids separate?
A. Prophase
B. Anaphase
C. Metaphase
D. Telophase
Rationale: Anaphase begins when cohesins are cleaved, allowing kinetochore
microtubules to pull sister chromatids toward opposite poles.
6. Which molecule is the final electron acceptor in the mitochondrial electron transport
chain?
A. NAD⁺
B. FAD
C. Oxygen
D. CO₂
Rationale: Oxygen accepts electrons and protons to form water; without it, the chain
backs up and ATP synthesis stops.
7. A cell with a 2N chromosome number of 8 will produce gametes with how many
chromosomes?
A. 2
B. 4
C. 8
D. 16
Rationale: Meiosis halves the chromosome number; 2N = 8 → N = 8 (haploid
gametes).
8. Which enzyme is responsible for unwinding the DNA double helix during replication?
A. DNA polymerase
B. Helicase
C. Ligase
D. Primase
Rationale: Helicase uses ATP to break hydrogen bonds between base pairs, creating
replication forks.
9. The primary function of the rough endoplasmic reticulum is:
A. Lipid synthesis
B. Synthesis and modification of membrane-bound and secretory proteins
C. ATP production
D. Carbohydrate storage
, Rationale: Ribosomes on the rough ER synthesize proteins that enter the ER lumen for
folding and glycosylation.
10.Which of the following is a purine base?
A. Cytosine
B. Thymine
C. Adenine
D. Uracil
Rationale: Purines (adenine and guanine) have a double-ring structure; pyrimidines
(C, T, U) have a single ring.
11.In the absence of oxygen, human muscle cells produce:
A. Ethanol
B. Lactate
C. Acetyl-CoA
D. Citrate
Rationale: Lactate is formed from pyruvate to regenerate NAD⁺ for glycolysis to
continue anaerobically.
12.Which intermediate links glycolysis and the citric acid cycle?
A. Acetaldehyde
B. Acetyl-CoA
C. Oxaloacetate
D. Pyruvate dehydrogenase
Rationale: Pyruvate is converted to acetyl-CoA by the pyruvate dehydrogenase
complex, feeding into the TCA cycle.
13.The net gain of ATP from one molecule of glucose during glycolysis is:
A. 1
B. 2
C. 4 (net 2)
D. 32
Rationale: 4 ATP produced – 2 ATP used = 2 net ATP per glucose.
14.Which of the following is NOT a component of the cell membrane?
A. Phospholipid
B. Cholesterol
C. Ribosome
D. Integral protein
Rationale: Ribosomes are non-membranous organelles that synthesize proteins; they
are not part of the lipid bilayer.
15.Which process generates the most ATP in aerobic respiration?
A. Glycolysis
B. Krebs cycle
C. Electron transport chain
D. Fermentation
Rationale: Oxidative phosphorylation via the ETC produces ~26–28 ATP per glucose.
16.Which of the following best describes facilitated diffusion?
A. Requires ATP
B. Passive movement of polar molecules via membrane proteins