BIO 101 Final Exam Practice — 148 Questions
2026–2027 Study Guide | Original Practice Questions
Questions 1–20: Foundations of Biology & Scientific Method
1. Which characteristic is shared by all living organisms?
A. Ability to move from place to place
B. Ability to maintain internal conditions
C. Ability to perform photosynthesis
D. Presence of a nucleus
Correct Answer: B
Rationale: All living organisms maintain some degree of homeostasis, regulating internal
conditions despite external changes. Not all organisms move, photosynthesize, or possess nuclei.
2. Which sequence correctly represents the scientific method?
A. Conclusion → hypothesis → observation → experiment
B. Observation → question → hypothesis → experiment → analysis
C. Experiment → observation → conclusion → hypothesis
D. Hypothesis → conclusion → question → observation
Correct Answer: B
Rationale: Scientific investigations commonly begin with observations and questions, followed
by a testable hypothesis, experimentation, data analysis, and conclusions.
3. A hypothesis must be:
A. Proven correct
B. Based only on opinion
C. Testable and potentially falsifiable
D. Accepted by everyone
Correct Answer: C
Rationale: A scientific hypothesis must make predictions that can be tested. A hypothesis that
cannot potentially be shown to be wrong is not scientifically testable.
,4. In an experiment testing whether fertilizer affects plant growth, what is the independent
variable?
A. Plant height
B. Amount of fertilizer
C. Type of plant
D. Amount of water
Correct Answer: B
Rationale: The independent variable is the factor deliberately changed by the researcher. Plant
height would be the dependent variable.
5. What is the dependent variable in the experiment above?
A. Fertilizer concentration
B. Soil type
C. Plant height
D. Plant species
Correct Answer: C
Rationale: The dependent variable is the measured outcome. Here, plant height is measured to
determine whether fertilizer produced an effect.
6. What is the primary purpose of a control group?
A. To increase the experimental variable
B. To provide a comparison
C. To eliminate all biological variation
D. To guarantee the hypothesis is correct
Correct Answer: B
Rationale: A control group provides a baseline against which experimental results can be
compared.
7. Which level of organization is immediately above the cellular level?
A. Organ
B. Tissue
C. Organ system
D. Organism
,Correct Answer: B
Rationale: Similar cells working together form tissues. The hierarchy includes molecules →
organelles → cells → tissues → organs → organ systems → organisms.
8. Which field primarily studies interactions between organisms and their environment?
A. Genetics
B. Ecology
C. Cytology
D. Anatomy
Correct Answer: B
Rationale: Ecology examines relationships among organisms and between organisms and their
physical environment.
9. A scientific theory is best described as:
A. A random guess
B. An untested idea
C. A well-supported explanation based on substantial evidence
D. A personal belief
Correct Answer: C
Rationale: Scientific theories are comprehensive explanations supported by extensive evidence
and repeated testing.
10. Which statement best describes homeostasis?
A. Maintaining stable internal conditions
B. Increasing body size
C. Producing offspring
D. Obtaining sunlight
Correct Answer: A
Rationale: Homeostasis allows organisms to maintain relatively stable internal conditions, such
as temperature, pH, and glucose concentration.
, 11. Which branch of biology focuses on heredity?
A. Ecology
B. Genetics
C. Taxonomy
D. Physiology
Correct Answer: B
Rationale: Genetics is the study of genes, heredity, and variation.
12. Which is an example of a quantitative observation?
A. The solution is blue
B. The organism appears healthy
C. The plant is 18 cm tall
D. The leaf feels rough
Correct Answer: C
Rationale: Quantitative observations involve numerical measurements.
13. Why are repeated trials important?
A. They eliminate the need for controls
B. They improve confidence in the results
C. They guarantee statistical significance
D. They prove causation automatically
Correct Answer: B
Rationale: Replication helps determine whether results are consistent rather than the result of
random variation or experimental error.
14. Which statement represents a prediction?
A. Plants require energy
B. Fertilizer affects growth
C. If fertilizer increases growth, fertilized plants will become taller
D. Plant growth was measured
Correct Answer: C
Rationale: A prediction states an expected outcome that can be tested experimentally.
2026–2027 Study Guide | Original Practice Questions
Questions 1–20: Foundations of Biology & Scientific Method
1. Which characteristic is shared by all living organisms?
A. Ability to move from place to place
B. Ability to maintain internal conditions
C. Ability to perform photosynthesis
D. Presence of a nucleus
Correct Answer: B
Rationale: All living organisms maintain some degree of homeostasis, regulating internal
conditions despite external changes. Not all organisms move, photosynthesize, or possess nuclei.
2. Which sequence correctly represents the scientific method?
A. Conclusion → hypothesis → observation → experiment
B. Observation → question → hypothesis → experiment → analysis
C. Experiment → observation → conclusion → hypothesis
D. Hypothesis → conclusion → question → observation
Correct Answer: B
Rationale: Scientific investigations commonly begin with observations and questions, followed
by a testable hypothesis, experimentation, data analysis, and conclusions.
3. A hypothesis must be:
A. Proven correct
B. Based only on opinion
C. Testable and potentially falsifiable
D. Accepted by everyone
Correct Answer: C
Rationale: A scientific hypothesis must make predictions that can be tested. A hypothesis that
cannot potentially be shown to be wrong is not scientifically testable.
,4. In an experiment testing whether fertilizer affects plant growth, what is the independent
variable?
A. Plant height
B. Amount of fertilizer
C. Type of plant
D. Amount of water
Correct Answer: B
Rationale: The independent variable is the factor deliberately changed by the researcher. Plant
height would be the dependent variable.
5. What is the dependent variable in the experiment above?
A. Fertilizer concentration
B. Soil type
C. Plant height
D. Plant species
Correct Answer: C
Rationale: The dependent variable is the measured outcome. Here, plant height is measured to
determine whether fertilizer produced an effect.
6. What is the primary purpose of a control group?
A. To increase the experimental variable
B. To provide a comparison
C. To eliminate all biological variation
D. To guarantee the hypothesis is correct
Correct Answer: B
Rationale: A control group provides a baseline against which experimental results can be
compared.
7. Which level of organization is immediately above the cellular level?
A. Organ
B. Tissue
C. Organ system
D. Organism
,Correct Answer: B
Rationale: Similar cells working together form tissues. The hierarchy includes molecules →
organelles → cells → tissues → organs → organ systems → organisms.
8. Which field primarily studies interactions between organisms and their environment?
A. Genetics
B. Ecology
C. Cytology
D. Anatomy
Correct Answer: B
Rationale: Ecology examines relationships among organisms and between organisms and their
physical environment.
9. A scientific theory is best described as:
A. A random guess
B. An untested idea
C. A well-supported explanation based on substantial evidence
D. A personal belief
Correct Answer: C
Rationale: Scientific theories are comprehensive explanations supported by extensive evidence
and repeated testing.
10. Which statement best describes homeostasis?
A. Maintaining stable internal conditions
B. Increasing body size
C. Producing offspring
D. Obtaining sunlight
Correct Answer: A
Rationale: Homeostasis allows organisms to maintain relatively stable internal conditions, such
as temperature, pH, and glucose concentration.
, 11. Which branch of biology focuses on heredity?
A. Ecology
B. Genetics
C. Taxonomy
D. Physiology
Correct Answer: B
Rationale: Genetics is the study of genes, heredity, and variation.
12. Which is an example of a quantitative observation?
A. The solution is blue
B. The organism appears healthy
C. The plant is 18 cm tall
D. The leaf feels rough
Correct Answer: C
Rationale: Quantitative observations involve numerical measurements.
13. Why are repeated trials important?
A. They eliminate the need for controls
B. They improve confidence in the results
C. They guarantee statistical significance
D. They prove causation automatically
Correct Answer: B
Rationale: Replication helps determine whether results are consistent rather than the result of
random variation or experimental error.
14. Which statement represents a prediction?
A. Plants require energy
B. Fertilizer affects growth
C. If fertilizer increases growth, fertilized plants will become taller
D. Plant growth was measured
Correct Answer: C
Rationale: A prediction states an expected outcome that can be tested experimentally.