Free ACT Science: Conflicting Viewpoints Questions and Answers 2 — Questions and Answers
Question 1: Scientist 1 argues that the observed acceleration in cosmic expansion is caused by dark energy — a repulsive force embedded in the fabric of space. Scientist 2 argues it results from a massive cosmic void through which our galaxy happens to be moving. The discovery that the acceleration rate is identical in all directions would most support:
- Scientist 1, because dark energy acts uniformly in all directions throughout space (Correct answer)
- Scientist 2, because voids extend uniformly outward from a center
- Neither scientist, since directional uniformity contradicts both theories
- Both scientists equally, as this data is consistent with either model
Correct answer: Scientist 1, because dark energy acts uniformly in all directions throughout space
Dark energy is theorized to be a property of space itself — it should act uniformly in every direction. A cosmic void would create directional variation (stronger effect toward the void's center). Uniform acceleration supports Scientist 1.
Question 2: Two ecologists disagree about wolf reintroduction in Yellowstone. Ecologist A says wolves restored the ecosystem by reducing overgrazing by elk. Ecologist B says river channel changes attributed to wolves were actually caused by climate shifts and rainfall changes. Which evidence would most strengthen Ecologist B's position?
- Records showing that river channel changes began before wolf reintroduction (Correct answer)
- Evidence that elk populations declined significantly after wolf reintroduction
- Documentation that wolves preferentially hunt near riverbanks
- Records showing that plant growth increased after wolves returned
Correct answer: Records showing that river channel changes began before wolf reintroduction
If river changes preceded wolf reintroduction, they cannot be caused by the wolves — this directly supports Ecologist B's argument that the changes had a different cause (climate/rainfall).
Question 3: Student 1 argues that the Moon formed from debris ejected when a Mars-sized body struck early Earth (Giant Impact Hypothesis). Student 2 argues the Moon was a separately formed body captured by Earth's gravity. The Moon's oxygen isotope ratios are nearly identical to Earth's. This evidence:
- Supports Student 1, since a collision would mix Earth's material into the Moon (Correct answer)
- Supports Student 2, since captured bodies have different isotope ratios from their captors
- Equally supports both students
- Contradicts both hypotheses
Correct answer: Supports Student 1, since a collision would mix Earth's material into the Moon
Identical oxygen isotope ratios suggest the Moon formed from the same material as Earth — consistent with the Giant Impact Hypothesis (Student 1). Captured foreign bodies typically have distinct isotope signatures.
Question 4: Researcher A claims a new insecticide is safe for bees because lab tests showed no bee mortality at recommended concentrations. Researcher B claims the insecticide is dangerous because field studies showed 40% colony collapse. Which methodological factor best explains the difference?
- Lab conditions cannot replicate complex field exposures — bees in the field encounter sublethal doses through food, water, and multiple routes simultaneously (Correct answer)
- Researcher A used higher concentrations than Researcher B
- Researcher B's field colonies were diseased before the study
- The recommended concentration was determined incorrectly by Researcher A
Correct answer: Lab conditions cannot replicate complex field exposures — bees in the field encounter sublethal doses through food, water, and multiple routes simultaneously
Lab tests isolate a single variable; field exposures are complex and cumulative. Sublethal but repeated exposures through pollen, water, and combined stressors can cause colony collapse even when single doses appear safe.
Question 5: Geologist 1 argues that the Grand Canyon was carved gradually over millions of years by the Colorado River. Geologist 2 argues it was carved rapidly by catastrophic flooding from a glacial lake overflow. Which finding would most support Geologist 1?
- Sediment layers within the canyon showing consistent, gradual deposition rates over millions of years (Correct answer)
- Evidence of giant ripple marks on the canyon floor typical of catastrophic floods
- Discovery of lake bed sediments upstream of the canyon
- Carbon dating of organic material in the canyon floor to 10,000 years ago
Correct answer: Sediment layers within the canyon showing consistent, gradual deposition rates over millions of years
Consistent gradual deposition over millions of years directly supports slow carving (Geologist 1). Giant ripple marks, lake bed sediments, and recent dating would support catastrophic flooding (Geologist 2).
Question 6: Scientist 1 proposes that declining bee populations are primarily due to pesticide use. Scientist 2 proposes habitat loss is the primary cause. A study finds that bee populations in areas with pesticide use but abundant wildflower corridors are stable, while populations in pesticide-free areas with reduced habitat are declining. This study:
- Supports Scientist 2, because habitat availability appears more critical than pesticide exposure to population stability (Correct answer)
- Conclusively proves Scientist 1 wrong
- Supports Scientist 1, because bees near pesticides still decline eventually
- Cannot be used to support either scientist
Correct answer: Supports Scientist 2, because habitat availability appears more critical than pesticide exposure to population stability
The study shows that habitat (abundant wildflowers) can offset pesticide effects, while its absence causes decline even without pesticides — suggesting habitat is the more critical variable, supporting Scientist 2.
Free ACT Science: Conflicting Viewpoints Questions and Answers 2
Scientist 1 argues that the observed acceleration in cosmic expansion is caused by dark energy — a repulsive force embedded in the fabric of space.
Scientist 2 argues it results from a massive cosmic void through which our galaxy happens to be moving.
The discovery that the acceleration rate is identical in all directions would most support: