WGU D850 General Biology I Lab (BIOL 1011)
Performance Assessment | Fully Worked PA
Study Exemplar + Rubric-Aligned Lab Report
Guide | 2026
WGU D850 General Biology I Lab (BIOL 1011) Performance Assessment Practice
Exam | 150 Questions with Correct Answers and Detailed Explanations | Rubric-
Aligned Study Guide | 2026
SECTION 1: Scientific Method and Experimental Design
1. A student is designing an experiment to test the effect of light intensity on
plant growth. The student places identical plants in different light conditions and
measures their height over four weeks. What is the independent variable in this
experiment?
A) Plant height
B) Light intensity
C) Type of plant
D) Duration of the experiment
Correct Answer: B
Explanation: The independent variable is the factor that the researcher
manipulates. In this experiment, the student manipulates light intensity. Plant
height is the dependent variable (what is measured). Type of plant and duration
are controlled variables.
,2. In the experiment described in Question 1, what is the dependent variable?
A) Plant height
B) Light intensity
C) Type of plant
D) Amount of water
Correct Answer: A
Explanation: The dependent variable is what the researcher measures. In this
case, the student measures plant height to determine the effect of light intensity.
The dependent variable "depends" on the independent variable.
3. A scientist wants to determine if a new fertilizer increases tomato yield. She
plants 50 tomato plants: 25 receive the new fertilizer, and 25 receive no
fertilizer. She measures the number of tomatoes produced by each plant. What
is the control group in this experiment?
A) The 25 plants that received the new fertilizer
B) The 25 plants that received no fertilizer
C) All 50 plants
D) The number of tomatoes produced
Correct Answer: B
Explanation: The control group is the group that does not receive the
experimental treatment. In this case, the 25 plants that received no fertilizer serve
as the control group, providing a baseline for comparison.
4. Which of the following is a properly stated hypothesis?
A) Does temperature affect enzyme activity?
B) If temperature increases, then enzyme activity will increase up to an optimal
point and then decrease.
,C) Temperature and enzyme activity.
D) Enzymes are affected by temperature.
Correct Answer: B
Explanation: A hypothesis should be a testable, falsifiable statement that predicts
the relationship between variables. Option B is properly formatted as an
"If...then..." statement. Option A is a question, not a hypothesis. Options C and D
are too vague.
5. A student conducts an experiment and obtains results that do not support the
hypothesis. What should the student do?
A) Change the data to support the hypothesis
B) Discard the experiment and start over
C) Report the results honestly and discuss possible reasons for the discrepancy
D) Modify the hypothesis to match the results
Correct Answer: C
Explanation: Scientific integrity requires honest reporting of results, even if they
do not support the hypothesis. The student should discuss possible reasons for
the discrepancy in the discussion section, such as experimental errors or
alternative explanations.
6. A researcher is studying the rotation of the molecular structure of a chiral
drug. She notices that one enantiomer is effective while the other is not. This
observation is an example of:
A) A controlled experiment
B) A qualitative observation
C) A hypothesis
D) A theory
Correct Answer: B
Explanation: The rotation of the molecular structure leading to different effects is
, a qualitative observation. The researcher observes a difference in effectiveness
between enantiomers. This observation could then lead to a hypothesis and
controlled experiments.
7. Which of the following is an example of a quantitative observation?
A) The solution turned blue.
B) The plant grew 5.2 cm in one week.
C) The leaf felt smooth.
D) The odor was pungent.
Correct Answer: B
Explanation: Quantitative observations involve numerical measurements. "5.2
cm" is a quantitative measurement. Options A, C, and D are qualitative
observations (descriptions without numbers).
8. In a controlled experiment, why is it important to have only one independent
variable?
A) To make the experiment easier to conduct
B) To ensure that any observed changes in the dependent variable are due to the
independent variable
C) To reduce the cost of the experiment
D) To increase the sample size
Correct Answer: B
Explanation: Having only one independent variable ensures that any changes in
the dependent variable can be attributed to that variable and not to confounding
factors. If multiple variables were changed simultaneously, it would be impossible
to determine which one caused the observed effect.
Performance Assessment | Fully Worked PA
Study Exemplar + Rubric-Aligned Lab Report
Guide | 2026
WGU D850 General Biology I Lab (BIOL 1011) Performance Assessment Practice
Exam | 150 Questions with Correct Answers and Detailed Explanations | Rubric-
Aligned Study Guide | 2026
SECTION 1: Scientific Method and Experimental Design
1. A student is designing an experiment to test the effect of light intensity on
plant growth. The student places identical plants in different light conditions and
measures their height over four weeks. What is the independent variable in this
experiment?
A) Plant height
B) Light intensity
C) Type of plant
D) Duration of the experiment
Correct Answer: B
Explanation: The independent variable is the factor that the researcher
manipulates. In this experiment, the student manipulates light intensity. Plant
height is the dependent variable (what is measured). Type of plant and duration
are controlled variables.
,2. In the experiment described in Question 1, what is the dependent variable?
A) Plant height
B) Light intensity
C) Type of plant
D) Amount of water
Correct Answer: A
Explanation: The dependent variable is what the researcher measures. In this
case, the student measures plant height to determine the effect of light intensity.
The dependent variable "depends" on the independent variable.
3. A scientist wants to determine if a new fertilizer increases tomato yield. She
plants 50 tomato plants: 25 receive the new fertilizer, and 25 receive no
fertilizer. She measures the number of tomatoes produced by each plant. What
is the control group in this experiment?
A) The 25 plants that received the new fertilizer
B) The 25 plants that received no fertilizer
C) All 50 plants
D) The number of tomatoes produced
Correct Answer: B
Explanation: The control group is the group that does not receive the
experimental treatment. In this case, the 25 plants that received no fertilizer serve
as the control group, providing a baseline for comparison.
4. Which of the following is a properly stated hypothesis?
A) Does temperature affect enzyme activity?
B) If temperature increases, then enzyme activity will increase up to an optimal
point and then decrease.
,C) Temperature and enzyme activity.
D) Enzymes are affected by temperature.
Correct Answer: B
Explanation: A hypothesis should be a testable, falsifiable statement that predicts
the relationship between variables. Option B is properly formatted as an
"If...then..." statement. Option A is a question, not a hypothesis. Options C and D
are too vague.
5. A student conducts an experiment and obtains results that do not support the
hypothesis. What should the student do?
A) Change the data to support the hypothesis
B) Discard the experiment and start over
C) Report the results honestly and discuss possible reasons for the discrepancy
D) Modify the hypothesis to match the results
Correct Answer: C
Explanation: Scientific integrity requires honest reporting of results, even if they
do not support the hypothesis. The student should discuss possible reasons for
the discrepancy in the discussion section, such as experimental errors or
alternative explanations.
6. A researcher is studying the rotation of the molecular structure of a chiral
drug. She notices that one enantiomer is effective while the other is not. This
observation is an example of:
A) A controlled experiment
B) A qualitative observation
C) A hypothesis
D) A theory
Correct Answer: B
Explanation: The rotation of the molecular structure leading to different effects is
, a qualitative observation. The researcher observes a difference in effectiveness
between enantiomers. This observation could then lead to a hypothesis and
controlled experiments.
7. Which of the following is an example of a quantitative observation?
A) The solution turned blue.
B) The plant grew 5.2 cm in one week.
C) The leaf felt smooth.
D) The odor was pungent.
Correct Answer: B
Explanation: Quantitative observations involve numerical measurements. "5.2
cm" is a quantitative measurement. Options A, C, and D are qualitative
observations (descriptions without numbers).
8. In a controlled experiment, why is it important to have only one independent
variable?
A) To make the experiment easier to conduct
B) To ensure that any observed changes in the dependent variable are due to the
independent variable
C) To reduce the cost of the experiment
D) To increase the sample size
Correct Answer: B
Explanation: Having only one independent variable ensures that any changes in
the dependent variable can be attributed to that variable and not to confounding
factors. If multiple variables were changed simultaneously, it would be impossible
to determine which one caused the observed effect.
