# ACT Science Biology Practice Strategies
Want to check your answers and get step-by-step solutions?
The ACT Science section gives you 35 minutes for 40 questions across 6-7 passages. Biology topics appear in all three passage types: Data Representation, Research Summaries, and Conflicting Viewpoints. This guide provides strategies to maximise your score.
1. General ACT Science Strategy
Time Management
- ~5 minutes per passage (including questions)
- Don't read the entire passage first — go to the questions
- Data Representation passages are usually quickest; start with those
- Save Conflicting Viewpoints for last (most reading required)
The "Question-First" Approach
- Skim the passage headings and figure titles (30 seconds)
- Read the first question
- Go to the relevant figure/table/paragraph to find the answer
- Move to the next question
- Only read the full passage if a question requires overall understanding
2. Strategies by Passage Type
Data Representation
- Focus on figures: Read axis labels, units, and legends
- Trace with your finger: Find specific values by tracing from one axis to the data point to the other axis
- Look for trends: Increasing, decreasing, cyclic, or no pattern
- Common biology graphs: growth curves, enzyme activity, heart rate over time
Research Summaries
- Identify the purpose of each experiment
- Note what changed between experiments (the IV)
- Compare results across experiments
- Don't get lost in procedure details — focus on what was measured and what happened
Conflicting Viewpoints
- Read both/all viewpoints before answering (this is the exception to question-first)
- Underline the key claim of each scientist/student
- Note the disagreement — most questions test whether you understand how the viewpoints differ
3. Biology-Specific Tips
Common Biology Topics on the ACT
- Cell biology and microscopy
- Genetics and inheritance (Punnett squares, pedigrees)
- Ecology (food webs, population growth, biodiversity)
- Evolution and natural selection
- Human physiology (enzymes, hormones, organ systems)
- Plant biology (photosynthesis, transpiration)
Biology Vocabulary to Know
| Term | Meaning |
|---|---|
| Hypothesis | Testable prediction |
| Variable | Factor that can change |
| Control group | No treatment (baseline) |
| In vitro | In the lab (outside organism) |
| In vivo | In a living organism |
| Phenotype | Observable characteristic |
| Genotype | Genetic makeup |
| Aerobic | Requires oxygen |
| Anaerobic | Without oxygen |
| Homeostasis | Maintaining stable internal conditions |
Reading Biology Graphs
- Growth curves often follow logistic (S-shape) or exponential (J-shape) patterns
- Enzyme graphs typically show a peak (optimum) and then decline
- Population cycles show oscillations with time lags between predator and prey
4. Common Mistakes to Avoid
- Using outside knowledge: The answer is always in the passage data
- Misreading axes: Check units and scales carefully (linear vs. logarithmic)
- Confusing correlation and causation: Data showing two things occur together doesn't mean one causes the other
- Over-generalising: If the experiment tested one species, don't conclude it applies to all organisms
- Rushing through figures: Take 10 extra seconds to understand a figure — it saves time on multiple questions
5. Practice Plan
Weekly Schedule (4 weeks before the test)
Week Focus Practice 1 Data Representation 3 passages/day; focus on speed 2 Research Summaries 2 passages/day; focus on experimental design 3 Conflicting Viewpoints 2 passages/day; focus on comparing viewpoints 4 Full practice tests 2 full Science sections under timed conditions Self-Assessment
- After each practice passage, review every wrong answer
- Ask: "Where in the passage was the answer?" (It's always there)
- Track your accuracy by passage type to identify weaknesses
- Aim for under 5 minutes per passage
Want to check your answers and get step-by-step solutions?
6. Practice Questions
Q1. A passage states: "Enzyme X activity was measured at pH 2, 4, 6, 7, 8, and 10. Activity was highest at pH 7 and decreased at all other pH values." Without seeing the data, which graph shape would you expect?
A1. A bell curve (inverted U-shape) with the peak at pH 7. Activity would be lower at both acidic and basic pH values, with the curve being roughly symmetrical around the optimum.
Q2. A Research Summary describes two experiments. Experiment 1 uses sunlight; Experiment 2 uses artificial UV light. All other conditions are the same. A question asks: "What is the most likely purpose of Experiment 2?"
A2. To test whether the effect observed in Experiment 1 is specifically due to UV light (a component of sunlight) rather than sunlight as a whole. Experiment 2 isolates the UV variable.
Want to check your answers and get step-by-step solutions?
Summary
- Use the question-first approach for Data Representation and Research Summaries
- Read all viewpoints before answering Conflicting Viewpoints questions
- Focus on data interpretation, not memorised content
- Manage your time: ~5 minutes per passage
- Avoid common traps: outside knowledge, misread axes, over-generalisation
- Practice regularly and review all mistakes