AP Biology Labs Explained: What You Need to Know for the Exam
AP Biology Labs Explained: What You Actually Need to Know for the Exam
TLDR
AP Biology requires significant lab work in class: at least 25 percent of instructional time, with a minimum of two investigations for each of the four Big Ideas. Teachers can use alternatives as long as they are inquiry-based.
The official AP Biology lab manual features 13 inquiry-based investigations that align to the course framework and science practices.
Exam questions do not ask you to recite lab steps. They test the skills those labs build: designing experiments, analyzing data, using statistics, and explaining results with evidence. These are the AP Biology science practices.
Why labs matter for your AP score
Labs are not a side activity. The Course Audit requires at least 25 percent of class time be hands-on and inquiry-based, with at least two labs for each Big Idea. That lab time builds the exact skills the exam grades: planning investigations, representing and analyzing data, running statistical tests, and making evidence-based claims.
The 13 official AP Biology investigations
These come from the College Board’s AP Biology Investigative Labs manual. Your teacher may use alternatives, but these titles show the core skill targets.
Artificial Selection
What to know: define a testable trait, set selection pressure, track generational change. Typical data: mean change per generation, rates, simple graphs.Mathematical Modeling: Hardy-Weinberg
What to know: p, q, p^2, 2pq, q^2, equilibrium conditions, how sampling or selection alters allele frequencies. Typical math: chi-square on genotype counts, allele-frequency updates.Comparing DNA Sequences with BLAST
What to know: similarity vs homology, how percent identity supports a cladogram, limits of database matches. Typical task: use sequence similarity to justify relatedness in a tree.Diffusion and Osmosis
What to know: direction of water movement, tonicity, how surface area to volume affects rate. Typical math: percent change in mass, water potential components when given values.Photosynthesis
What to know: variables that affect rate (light, CO2, temperature), how to measure O2 production or CO2 uptake. Typical math: slope from O2 or disk-float time vs light intensity.Cellular Respiration
What to know: O2 consumption or CO2 production as rate of respiration, temperature controls, role of germinating vs non-germinating seeds. Typical math: rate = Δvolume per minute, corrected for temperature/pressure when provided.Cell Division: Mitosis and Meiosis
What to know: time spent in each stage, sources of genetic variation, nondisjunction concepts. Typical math: proportion of cells per stage, expected ratios vs observed in crosses.Biotechnology: Bacterial Transformation
What to know: plasmids, selection markers, gene expression, transformation efficiency. Typical math: colonies per microgram DNA, percent transformed.Biotechnology: Restriction Enzyme Analysis of DNA
What to know: restriction sites, fragment sizes, reading gel patterns. Typical math: estimate base pairs from a standard curve, justify a map that matches banding patterns.Energy Dynamics
What to know: trophic levels, energy transfer, production vs biomass. Typical math: NPP = GPP − R, percent transfer between levels.Transpiration
What to know: how humidity, temperature, light, and wind affect water loss, role of stomata and xylem tension. Typical math: transpiration rate per leaf area, graph rate vs condition.Fruit Fly Behavior (Animal Behavior)
What to know: innate vs learned behavior, taxis and kinesis, experimental design with controls. Typical math: chi-square on observed vs expected choices in a chamber.Enzyme Activity
What to know: how pH, temperature, and substrate concentration affect rate, denaturation vs inhibition. Typical math: initial rate from product vs time, compare treatments with error bars.
(Full titles and links are listed on AP Central’s “Investigative Labs: Comprehensive Links” page.) AP Central
How labs show up on the AP exam
The exam uses the science practices embedded in those labs. Expect tasks that ask you to:
Identify a testable question and state a hypothesis.
Design an experiment with variables, controls, and a method that yields analyzable data.
Represent data correctly: choose labels, units, scales, and error bars.
Run simple statistics or math when prompted: mean, standard error, chi-square, rates, percent change.
Make a claim, support it with evidence from the data, and explain the reasoning that links them.
Quick lab-to-exam cheat sheet
Use this as a weekly drill list.
Chi-square appears with genetics, behavior choice tests, and Hardy-Weinberg tables.
Rates and slopes appear with photosynthesis, respiration, enzymes, transpiration, and population growth.
Gel interpretation appears with restriction analysis and sometimes transformation confirmation.
Graph literacy shows up everywhere: axes, units, trend statements, and justifying models with data.
Experimental design is common: identify variables, improve a flawed method, or predict results of a change.
Study plan that targets labs
Pick two lab themes per week. Re-graph sample data, calculate one rate or statistic, then write a 3-sentence Claim-Evidence-Reasoning summary.
Practice one FRQ that involves experimental design or data analysis. Grade yourself with the rubric language: identify the point for each sentence.
Create a formula flash card set for water potential, chi-square, Hardy-Weinberg, and productivity. Tie each to a lab where it appears.
For biotech labs, practice reading a gel and calculating transformation efficiency from a short scenario.
Want focused help turning lab work into FRQ points? Our tutors drill the exact skills above and show you how to write responses that earn rubric points fast.
