ACT Science · 1 Full Passage per Exam (7 Questions, ~18% of Science Score)
Conflicting Viewpoints & Hypothesis Comparison
Key ACT Science Strategy at a Glance
The Conflicting Viewpoints passage contains no graphs or charts—only competing textual theories (Scientist 1 vs Scientist 2 or Student 1, 2, 3). Do not read the full passage upfront. Spend 60 seconds reading the introductory paragraph and identifying the central disagreement. Then answer single-perspective questions first, saving comparison questions for last.
1. The 3 Question Categories on Conflicting Viewpoints
Every Conflicting Viewpoints passage features 7 questions divided into three predictable categories:
Single-Scientist Detail
"According to Scientist 1, what caused..." Answer these first. Scan solely Scientist 1's paragraph to extract the stated claim.
New Evidence / Hypothetical Impact
"If discovery X were made, which scientist would it support?" Look for the hypothesis whose mechanism matches discovery X.
Direct Point of Disagreement
"Scientist 1 and Scientist 2 would most likely agree/disagree on which point?" Identify common ground vs core dispute.
6 Minutes Maximum
You have 35 minutes for 40 questions (approx. 5.5 minutes per passage). Never spend more than 6.5 minutes on Viewpoints.
ACT Science passages deliberately include intimidating chemical names, geological epochs, and theoretical terms (e.g., paleomagnetic declination, serpentine subduction). You do not need prior knowledge of these terms! Focus solely on relationships: Does Variable A cause Variable B? Does Scientist 1 say Yes while Scientist 2 says No?
2. The 3-Step Execution Sequence
- Read the Introduction Only: Determine what phenomenon is being debated (e.g., "Origin of Earth's Moon" or "Mechanism of Enzyme Inhibition").
- Tag Each Perspective with 2 Words:
- Scientist 1: Giant impact / Earth-Mars collision.
- Scientist 2: Fission theory / centrifugal separation.
- Triage Questions: Attack questions mentioning "Scientist 1 only", then "Scientist 2 only", and finally "Both scientists". This saves 90+ seconds per passage.
Official-Style ACT Science Practice
Question: Two biochemists debate how deep-sea hydrothermal vent bacteria synthesize carbohydrates without sunlight. Biochemist 1 argues the bacteria use sulfur oxidation (chemosynthesis) driven by hydrogen sulfide released from magma. Biochemist 2 argues the bacteria rely on radiolytic hydrogen gas generated by the radioactive decay of basalt rock. Which experimental result would present a major challenge to Biochemist 2's model?
View Step-by-Step Solution & Logic
Correct Answer: B
Biochemist 2's Core Premise: Carbohydrate synthesis relies on radiolytic hydrogen produced by radioactive decay in basalt rock.
Challenge to the Premise: If bacteria thrive where basalt rock has near-zero radioactive isotope concentrations, there is no radiation to generate radiolytic hydrogen! This invalidates Biochemist 2's necessary condition.
Why A is wrong: Supports Biochemist 1, but doesn't challenge Biochemist 2.
Why C is wrong: Temperature is not the contested fuel source.
Why D is wrong: Supports Biochemist 2 by proving basalt contains radioactive elements.
Train this skill with active recall
Mindupload trains pacing and hypothesis comparison on official-format ACT Science passages.
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