WGU D850 GENERAL BIOLOGY I LAB (BIOL 1011)
PERFORMANCE ASSESSMENT – 100 ORIGINAL
QUESTIONS AND ANSWERS | SCIENTIFIC
METHOD, EXPERIMENTAL DESIGN, VARIABLES
AND CONTROLS, LABORATORY PROTOCOLS AND
ETHICS, DATA COLLECTION AND ANALYSIS,
SIMULATED LAB REPORT COMPONENTS, RESULTS
INTERPRETATION, CONCLUSIONS, CRITICAL
THINKING, AND FURTHER RESEARCH |
2026/2027 LATEST UPDATE
SECTION 1: Scientific Investigation, Scientific Method, and Hypothesis Development
Questions 1–15
WGU's published D850 description specifically emphasizes applying the scientific method to
biological questions through hypothesis-driven experimentation.
1. Which statement best describes the primary purpose of scientific investigation in a
biology laboratory?
A) To confirm that an investigator's original belief is correct
B) To collect evidence that can be used to answer a biological question
C) To eliminate the need for repeated experimentation
D) To produce results that agree with previously published studies
Correct Answer: To collect evidence that can be used to answer a biological question
Rationale: Scientific investigation uses systematic observation and experimentation to obtain
evidence about a question. The purpose is not to guarantee that an initial belief is correct,
because evidence may contradict the original expectation. Reliable investigations allow
conclusions to be based on measurable observations rather than personal assumptions or
preferences.
,2. What characteristic makes a biological question especially appropriate for experimental
investigation?
A) It can be answered using personal opinion.
B) It has only one possible explanation.
C) It can be examined through measurable evidence.
D) It does not require variables to be identified.
Correct Answer: It can be examined through measurable evidence.
Rationale: An experimentally useful question can be investigated by collecting observable or
measurable evidence. Questions based entirely on opinion cannot be tested scientifically
because they lack objective measurements. Identifying measurable outcomes also helps
researchers select appropriate variables, controls, procedures, and methods for analyzing
the resulting evidence.
3. A researcher observes that seedlings placed near a window appear taller than seedlings
kept farther from the window. What should most appropriately follow this observation?
A) Formulate a testable hypothesis about light exposure and growth.
B) Immediately conclude that light caused the difference.
C) Discard the observation because it was not measured initially.
D) Change several environmental factors simultaneously.
Correct Answer: Formulate a testable hypothesis about light exposure and growth.
Rationale: An observation can lead to a hypothesis that proposes a possible explanation for
the observed pattern. The researcher should not immediately claim causation because other
factors may explain the difference. A well-designed experiment can then test whether
changing light exposure produces a measurable change in seedling growth.
4. Which hypothesis is most scientifically testable?
A) Plants are interesting organisms.
B) Plants should receive more sunlight.
C) Sunlight is important to life.
D) Increasing light exposure will increase the average growth of bean seedlings.
Correct Answer: Increasing light exposure will increase the average growth of bean
seedlings.
,Rationale: A testable hypothesis predicts a measurable relationship between variables. The
proposed hypothesis identifies light exposure as the factor being changed and seedling
growth as the measurable outcome. The other statements are broad opinions or general
claims that do not specify an experimentally measurable prediction.
5. What is the principal difference between an observation and a hypothesis?
A) An observation is evidence collected, whereas a hypothesis is a testable explanation.
B) An observation must always be numerical, whereas a hypothesis must always be verbal.
C) An observation is always correct, whereas a hypothesis cannot be tested.
D) An observation occurs after the conclusion, whereas a hypothesis occurs afterward.
Correct Answer: An observation is evidence collected, whereas a hypothesis is a testable
explanation.
Rationale: Observations describe information obtained through the senses or instruments,
while hypotheses propose explanations that can be tested. Observations may be qualitative
or quantitative. A hypothesis is not automatically true; its value depends on whether
experimental evidence supports or contradicts its prediction.
6. Why is a hypothesis described as tentative?
A) It cannot ever be supported by evidence.
B) It represents a proposed explanation that remains subject to testing.
C) It must always be based on numerical measurements.
D) It is written only after the experiment has been completed.
Correct Answer: It represents a proposed explanation that remains subject to testing.
Rationale: A hypothesis is tentative because it is a proposed explanation rather than an
established fact. Experimental evidence may support the prediction or reveal that the
proposed explanation is inadequate. Treating hypotheses as tentative helps researchers
avoid allowing expectations to determine how results are interpreted.
7. Which sequence most closely represents a logical scientific investigation?
A) Conclusion → observation → hypothesis → experiment
B) Experiment → conclusion → question → observation
C) Observation/question → hypothesis → experiment → analysis → conclusion
D) Hypothesis → conclusion → observation → experiment
, Correct Answer: Observation/question → hypothesis → experiment → analysis →
conclusion
Rationale: Scientific investigations generally begin with observations or questions and
develop a testable hypothesis. Researchers then conduct an experiment, analyze the
resulting evidence, and draw a conclusion based on that evidence. Although scientific work
can be iterative, this sequence represents the fundamental logic of hypothesis-driven
investigation.
8. A researcher predicts that increasing fertilizer concentration will increase plant height.
Which part of the statement is the prediction?
A) The existence of plants
B) The fertilizer itself
C) The measurement of height
D) Increased fertilizer concentration will increase plant height
Correct Answer: Increased fertilizer concentration will increase plant height
Rationale: The prediction describes the expected relationship between the manipulated
factor and the measured outcome. Fertilizer concentration is the factor being changed, while
plant height is the response being measured. A clear prediction helps determine what
observations would constitute evidence supporting or contradicting the hypothesis.
9. Why should a hypothesis be established before examining experimental results?
A) To guarantee a statistically significant outcome
B) To prevent the researcher from changing the procedure afterward
C) To reduce the risk of interpreting results according to a desired outcome
D) To ensure the hypothesis will be accepted
Correct Answer: To reduce the risk of interpreting results according to a desired outcome
Rationale: Establishing the hypothesis beforehand helps separate the original prediction
from the results obtained. If researchers create explanations only after seeing the data, they
may unintentionally interpret findings in a way that favors their expectations. Predefined
hypotheses promote more objective and transparent scientific reasoning.
10. Which statement represents a null hypothesis in an experiment comparing two light
conditions?
A) Light exposure will increase plant growth.
B) Plants receiving more light will grow taller.
PERFORMANCE ASSESSMENT – 100 ORIGINAL
QUESTIONS AND ANSWERS | SCIENTIFIC
METHOD, EXPERIMENTAL DESIGN, VARIABLES
AND CONTROLS, LABORATORY PROTOCOLS AND
ETHICS, DATA COLLECTION AND ANALYSIS,
SIMULATED LAB REPORT COMPONENTS, RESULTS
INTERPRETATION, CONCLUSIONS, CRITICAL
THINKING, AND FURTHER RESEARCH |
2026/2027 LATEST UPDATE
SECTION 1: Scientific Investigation, Scientific Method, and Hypothesis Development
Questions 1–15
WGU's published D850 description specifically emphasizes applying the scientific method to
biological questions through hypothesis-driven experimentation.
1. Which statement best describes the primary purpose of scientific investigation in a
biology laboratory?
A) To confirm that an investigator's original belief is correct
B) To collect evidence that can be used to answer a biological question
C) To eliminate the need for repeated experimentation
D) To produce results that agree with previously published studies
Correct Answer: To collect evidence that can be used to answer a biological question
Rationale: Scientific investigation uses systematic observation and experimentation to obtain
evidence about a question. The purpose is not to guarantee that an initial belief is correct,
because evidence may contradict the original expectation. Reliable investigations allow
conclusions to be based on measurable observations rather than personal assumptions or
preferences.
,2. What characteristic makes a biological question especially appropriate for experimental
investigation?
A) It can be answered using personal opinion.
B) It has only one possible explanation.
C) It can be examined through measurable evidence.
D) It does not require variables to be identified.
Correct Answer: It can be examined through measurable evidence.
Rationale: An experimentally useful question can be investigated by collecting observable or
measurable evidence. Questions based entirely on opinion cannot be tested scientifically
because they lack objective measurements. Identifying measurable outcomes also helps
researchers select appropriate variables, controls, procedures, and methods for analyzing
the resulting evidence.
3. A researcher observes that seedlings placed near a window appear taller than seedlings
kept farther from the window. What should most appropriately follow this observation?
A) Formulate a testable hypothesis about light exposure and growth.
B) Immediately conclude that light caused the difference.
C) Discard the observation because it was not measured initially.
D) Change several environmental factors simultaneously.
Correct Answer: Formulate a testable hypothesis about light exposure and growth.
Rationale: An observation can lead to a hypothesis that proposes a possible explanation for
the observed pattern. The researcher should not immediately claim causation because other
factors may explain the difference. A well-designed experiment can then test whether
changing light exposure produces a measurable change in seedling growth.
4. Which hypothesis is most scientifically testable?
A) Plants are interesting organisms.
B) Plants should receive more sunlight.
C) Sunlight is important to life.
D) Increasing light exposure will increase the average growth of bean seedlings.
Correct Answer: Increasing light exposure will increase the average growth of bean
seedlings.
,Rationale: A testable hypothesis predicts a measurable relationship between variables. The
proposed hypothesis identifies light exposure as the factor being changed and seedling
growth as the measurable outcome. The other statements are broad opinions or general
claims that do not specify an experimentally measurable prediction.
5. What is the principal difference between an observation and a hypothesis?
A) An observation is evidence collected, whereas a hypothesis is a testable explanation.
B) An observation must always be numerical, whereas a hypothesis must always be verbal.
C) An observation is always correct, whereas a hypothesis cannot be tested.
D) An observation occurs after the conclusion, whereas a hypothesis occurs afterward.
Correct Answer: An observation is evidence collected, whereas a hypothesis is a testable
explanation.
Rationale: Observations describe information obtained through the senses or instruments,
while hypotheses propose explanations that can be tested. Observations may be qualitative
or quantitative. A hypothesis is not automatically true; its value depends on whether
experimental evidence supports or contradicts its prediction.
6. Why is a hypothesis described as tentative?
A) It cannot ever be supported by evidence.
B) It represents a proposed explanation that remains subject to testing.
C) It must always be based on numerical measurements.
D) It is written only after the experiment has been completed.
Correct Answer: It represents a proposed explanation that remains subject to testing.
Rationale: A hypothesis is tentative because it is a proposed explanation rather than an
established fact. Experimental evidence may support the prediction or reveal that the
proposed explanation is inadequate. Treating hypotheses as tentative helps researchers
avoid allowing expectations to determine how results are interpreted.
7. Which sequence most closely represents a logical scientific investigation?
A) Conclusion → observation → hypothesis → experiment
B) Experiment → conclusion → question → observation
C) Observation/question → hypothesis → experiment → analysis → conclusion
D) Hypothesis → conclusion → observation → experiment
, Correct Answer: Observation/question → hypothesis → experiment → analysis →
conclusion
Rationale: Scientific investigations generally begin with observations or questions and
develop a testable hypothesis. Researchers then conduct an experiment, analyze the
resulting evidence, and draw a conclusion based on that evidence. Although scientific work
can be iterative, this sequence represents the fundamental logic of hypothesis-driven
investigation.
8. A researcher predicts that increasing fertilizer concentration will increase plant height.
Which part of the statement is the prediction?
A) The existence of plants
B) The fertilizer itself
C) The measurement of height
D) Increased fertilizer concentration will increase plant height
Correct Answer: Increased fertilizer concentration will increase plant height
Rationale: The prediction describes the expected relationship between the manipulated
factor and the measured outcome. Fertilizer concentration is the factor being changed, while
plant height is the response being measured. A clear prediction helps determine what
observations would constitute evidence supporting or contradicting the hypothesis.
9. Why should a hypothesis be established before examining experimental results?
A) To guarantee a statistically significant outcome
B) To prevent the researcher from changing the procedure afterward
C) To reduce the risk of interpreting results according to a desired outcome
D) To ensure the hypothesis will be accepted
Correct Answer: To reduce the risk of interpreting results according to a desired outcome
Rationale: Establishing the hypothesis beforehand helps separate the original prediction
from the results obtained. If researchers create explanations only after seeing the data, they
may unintentionally interpret findings in a way that favors their expectations. Predefined
hypotheses promote more objective and transparent scientific reasoning.
10. Which statement represents a null hypothesis in an experiment comparing two light
conditions?
A) Light exposure will increase plant growth.
B) Plants receiving more light will grow taller.
