BIOL 180 COMPLETE EXAM BUNDLE
2026/2027 | Exam 1 + Exam 2 +
Midterm Assessment + Final Exam
Review +, Study Guide & Verified
Answers | Lates update
Contents
EXAM 1 .................................................................................. 1
EXAM 2 .............................................................................. 38
Midterm exam...................................................................... 76
FINAL EXAM .................................................................. 116
MOST TESTED QUESTIONS .................................................. 155
EXAM 1
Question 1 – Levels of organization & emergent properties
In a coastal marsh ecosystem, a biologist measures the productivity of different
areas and notes that the introduction of a single invasive plant species causes a
decline in native bird populations, changes in nutrient cycling, and altered water
retention. The invasive plant has no major effect on individual marsh plants when
grown alone in pots.
Which conclusion best illustrates the concept of emergent properties and levels of
biological organization?
,A. The properties of individual plants fully explain all ecosystem changes
B. The ecosystem’s properties arise from interactions among species, not from any
single organism alone
C. The population level is irrelevant because ecosystems only depend on abiotic
factors
D. Emergent properties can only be observed at the molecular level, not at
ecosystem level
Answer: B. The ecosystem’s properties arise from interactions among species, not
from any single organism alone
Rationale: Emergent properties are new characteristics that arise at higher levels
of organization (e.g., ecosystems) that cannot be predicted by examining
individual components alone. Here, interactions among multiple populations
(plants, birds, microbes) and abiotic factors create ecosystem-level changes, even
though individual plants in isolation appear unaffected.
Question 2 – Hypotheses vs theories & testability
A researcher observes that a particular frog species has brightly colored skin and
tends to suffer less predation than other frog species in the same pond. She
proposes:
“Bright coloration in this frog species evolved because predators learned to
associate the color with toxicity, so frogs with brighter skin had greater
reproductive success.”
Which statement most accurately evaluates this explanation?
A. It is a testable hypothesis because it can be examined using predator-prey
experiments and toxicity assays
B. It is a scientific law because it describes a universal pattern that never changes
C. It is not scientific because it mentions evolution and behavior
D. It is an untestable opinion and cannot be investigated empirically
Answer: A. It is a testable hypothesis because it can be examined using
predator-prey experiments and toxicity assays
Rationale: The statement proposes a causal relationship that can be tested by
,measuring toxicity, predator behavior, and reproductive success. It is not a law or
untestable opinion; it’s a specific evolutionary hypothesis.
Question 3 – Experimental design & confounding variables
A scientist wants to test whether a new plant growth regulator increases tomato
yield. She plants 200 tomato plants in identical pots and randomly assigns them to
two groups: one treated weekly with the regulator, and one given plain water.
However, all regulator-treated plants are placed near a window, and all control
plants are placed near a shaded wall.
Which is the best critique of this experimental design?
A. Sample size is too large, making results meaningless
B. Light exposure is a confounding variable because it differs systematically
between treatment and control
C. Water should never be given to control plants
D. Random assignment eliminates all possible bias
Answer: B. Light exposure is a confounding variable because it differs
systematically between treatment and control
Rationale: Differences in light between groups could independently affect yield,
making it impossible to attribute any observed differences solely to the growth
regulator. Treatment and control groups must be exposed to the same conditions
except for the independent variable.
Question 4 – Interpreting p-values & significance
A study tests whether a new enzyme supplement improves lactose digestion in
adults. Researchers measure blood glucose increase after lactose ingestion with
and without the supplement in 100 participants. The mean increase is significantly
higher with supplementation (p = 0.0005).
Which interpretation of the p-value is most accurate?
A. There is a 0.05% chance that the observed difference is due to random
variation under the null hypothesis
B. The supplement is guaranteed to work for every individual
, C. The null hypothesis is proven false
D. The supplement cannot be effective because p is so small
Answer: A. There is a 0.05% chance that the observed difference is due to random
variation under the null hypothesis
Rationale: A p-value of 0.0005 means that, if the null hypothesis (no difference)
were true, the likelihood of obtaining data this extreme by chance is 0.05%. It
does not “prove” the null false or guarantee effectiveness for every person, but
strongly supports the alternative hypothesis.
Question 5 – Controls & scientific method
A researcher studying antibiotic resistance grows two bacterial strains: one with a
known resistance gene and one without. Both are exposed to increasing
concentrations of an antibiotic. The resistant strain survives higher concentrations,
while the non-resistant strain dies at low concentrations.
In this experimental design, what role does the non-resistant strain serve?
A. Independent variable
B. Negative control
C. Dependent variable
D. Confounding factor
Answer: B. Negative control
Rationale: The non-resistant strain is expected to be sensitive to the antibiotic and
serves as a negative control to confirm the assay’s ability to detect resistance
differences. The independent variable is antibiotic concentration; survival is the
dependent variable.
Question 6 – Macromolecules & structure–function
A cell biologist isolates a macromolecule that is rich in nitrogen but poor in
phosphorus, and finds that it folds into complex three-dimensional shapes and
binds specific substrates, speeding chemical reactions.
Which macromolecule is most likely being described, and why?
A. DNA, because nitrogen-rich bases catalyze reactions
2026/2027 | Exam 1 + Exam 2 +
Midterm Assessment + Final Exam
Review +, Study Guide & Verified
Answers | Lates update
Contents
EXAM 1 .................................................................................. 1
EXAM 2 .............................................................................. 38
Midterm exam...................................................................... 76
FINAL EXAM .................................................................. 116
MOST TESTED QUESTIONS .................................................. 155
EXAM 1
Question 1 – Levels of organization & emergent properties
In a coastal marsh ecosystem, a biologist measures the productivity of different
areas and notes that the introduction of a single invasive plant species causes a
decline in native bird populations, changes in nutrient cycling, and altered water
retention. The invasive plant has no major effect on individual marsh plants when
grown alone in pots.
Which conclusion best illustrates the concept of emergent properties and levels of
biological organization?
,A. The properties of individual plants fully explain all ecosystem changes
B. The ecosystem’s properties arise from interactions among species, not from any
single organism alone
C. The population level is irrelevant because ecosystems only depend on abiotic
factors
D. Emergent properties can only be observed at the molecular level, not at
ecosystem level
Answer: B. The ecosystem’s properties arise from interactions among species, not
from any single organism alone
Rationale: Emergent properties are new characteristics that arise at higher levels
of organization (e.g., ecosystems) that cannot be predicted by examining
individual components alone. Here, interactions among multiple populations
(plants, birds, microbes) and abiotic factors create ecosystem-level changes, even
though individual plants in isolation appear unaffected.
Question 2 – Hypotheses vs theories & testability
A researcher observes that a particular frog species has brightly colored skin and
tends to suffer less predation than other frog species in the same pond. She
proposes:
“Bright coloration in this frog species evolved because predators learned to
associate the color with toxicity, so frogs with brighter skin had greater
reproductive success.”
Which statement most accurately evaluates this explanation?
A. It is a testable hypothesis because it can be examined using predator-prey
experiments and toxicity assays
B. It is a scientific law because it describes a universal pattern that never changes
C. It is not scientific because it mentions evolution and behavior
D. It is an untestable opinion and cannot be investigated empirically
Answer: A. It is a testable hypothesis because it can be examined using
predator-prey experiments and toxicity assays
Rationale: The statement proposes a causal relationship that can be tested by
,measuring toxicity, predator behavior, and reproductive success. It is not a law or
untestable opinion; it’s a specific evolutionary hypothesis.
Question 3 – Experimental design & confounding variables
A scientist wants to test whether a new plant growth regulator increases tomato
yield. She plants 200 tomato plants in identical pots and randomly assigns them to
two groups: one treated weekly with the regulator, and one given plain water.
However, all regulator-treated plants are placed near a window, and all control
plants are placed near a shaded wall.
Which is the best critique of this experimental design?
A. Sample size is too large, making results meaningless
B. Light exposure is a confounding variable because it differs systematically
between treatment and control
C. Water should never be given to control plants
D. Random assignment eliminates all possible bias
Answer: B. Light exposure is a confounding variable because it differs
systematically between treatment and control
Rationale: Differences in light between groups could independently affect yield,
making it impossible to attribute any observed differences solely to the growth
regulator. Treatment and control groups must be exposed to the same conditions
except for the independent variable.
Question 4 – Interpreting p-values & significance
A study tests whether a new enzyme supplement improves lactose digestion in
adults. Researchers measure blood glucose increase after lactose ingestion with
and without the supplement in 100 participants. The mean increase is significantly
higher with supplementation (p = 0.0005).
Which interpretation of the p-value is most accurate?
A. There is a 0.05% chance that the observed difference is due to random
variation under the null hypothesis
B. The supplement is guaranteed to work for every individual
, C. The null hypothesis is proven false
D. The supplement cannot be effective because p is so small
Answer: A. There is a 0.05% chance that the observed difference is due to random
variation under the null hypothesis
Rationale: A p-value of 0.0005 means that, if the null hypothesis (no difference)
were true, the likelihood of obtaining data this extreme by chance is 0.05%. It
does not “prove” the null false or guarantee effectiveness for every person, but
strongly supports the alternative hypothesis.
Question 5 – Controls & scientific method
A researcher studying antibiotic resistance grows two bacterial strains: one with a
known resistance gene and one without. Both are exposed to increasing
concentrations of an antibiotic. The resistant strain survives higher concentrations,
while the non-resistant strain dies at low concentrations.
In this experimental design, what role does the non-resistant strain serve?
A. Independent variable
B. Negative control
C. Dependent variable
D. Confounding factor
Answer: B. Negative control
Rationale: The non-resistant strain is expected to be sensitive to the antibiotic and
serves as a negative control to confirm the assay’s ability to detect resistance
differences. The independent variable is antibiotic concentration; survival is the
dependent variable.
Question 6 – Macromolecules & structure–function
A cell biologist isolates a macromolecule that is rich in nitrogen but poor in
phosphorus, and finds that it folds into complex three-dimensional shapes and
binds specific substrates, speeding chemical reactions.
Which macromolecule is most likely being described, and why?
A. DNA, because nitrogen-rich bases catalyze reactions
