90 min
Multiple choice
60 questions · 50%
- Discrete items and sets of 4–5 on one graph, table, or experiment
- About 90 seconds a question
- Bluebook. No penalty for guessing
AP Biology Study Guide
Spend review time where the exam does: Natural Selection, Cellular Energetics, and Gene Expression. Stop rereading the chapter. Practice graphs and free-response until you can write the because.
Units 3, 6, 7 carry the mass.
The exam is two equal halves.
Three hours. Two 90-minute sections. Each is 50% of the score. The AP Biology exam is hybrid digital: multiple choice in Bluebook, free-response handwritten in a paper booklet. A calculator is allowed on both.
90 min
Free response
6 questions · 50%
- 2 long at 9 points · 4 short at 4 points
- Read the prompt on screen, write in the booklet
- Partial credit. Answer every lettered part
Eight units. Unequal weight.
College Board publishes how much each unit contributes to the multiple-choice section. Use that as a budget, not a permission slip to skip Unit 1. Select a column.
Unit 1 · Chemistry of Life 8–11% of MCQ Water, hydrogen bonding, macromolecules. Needed as a base. Not where most of the score lives.
Unit 2 · Cells 10–13% of MCQ Membranes, transport, cell size, compartmentalization. Shows up again in energetics and signaling.
Unit 3 · Cellular Energetics 12–16% of MCQ Enzymes, respiration, photosynthesis, free energy. High weight. Students lose points on pathways as systems, not lists.
Unit 4 · Cell Communication and Cell Cycle 10–15% of MCQ Signal transduction, feedback, mitosis, regulation. Expect disrupted pathways, not vocabulary matching.
Unit 5 · Heredity 8–11% of MCQ Meiosis, Mendelian and non-Mendelian inheritance, chi-square. Lower weight, still a reliable FRQ math ask.
Unit 6 · Gene Expression and Regulation 12–16% of MCQ Replication, transcription, translation, regulation, mutations. High weight. Tell the story of a gene under a change.
Unit 7 · Natural Selection 13–20% of MCQ Mechanisms of evolution, Hardy-Weinberg, phylogeny, speciation. The single heaviest unit. Start review here if time is short.
Unit 8 · Ecology 10–15% of MCQ Energy flow, populations, communities, disruptions. Graphs of density and diversity show up on both halves.
How to study for AP Biology.
The exam grades application: a graph you have not seen, a pathway with one piece knocked out. A highlighted textbook page does not train that. Close the notes. Then write.
01
Close the notes
After a unit, write the process from memory: inputs, outputs, where it lives in the cell. If you cannot, you do not have it yet. That retrieval loop is how to study with AI — a quiz from your own page, not a generated summary.
02
Read the graph
Name the axes, the trend, then the biology. Membranes connect to energetics; energetics connect to ecology. The same gradient idea keeps showing up. Start there, not with the vocab list.
03
Write the because
Rubrics pay for cause. “The cell uses ATP” is zero. “The cell uses ATP because active transport against a gradient requires energy” is the point. Say it out loud, then put it on paper.
A photo of those notes can become a quiz in Stephen AI — the retrieval half of an AP Biology study guide. College Board released FRQs stay the writing practice.
How AP Bio FRQs are scored.
Six questions, 90 minutes, half the exam. Long questions want experimental reasoning. Short ones each test one science practice. Work past prompts from AP Central against the scoring guidelines — that is the official rehearsal, not a Qbank stand-in.
Long · 9 points
Interpret experimental results
Identify the question, the variables, the control. State what the data show, then justify with the mechanism. Leave no lettered part blank.
Long · 9 points
Experimental results with graphing
Plot what the prompt asks — labeled axes, units, a line or bars that match the data. Then interpret. Practice this on paper. You will not type it.
Short · 4
Scientific investigation
Design or critique a method. Independent variable, control, what you would measure.
Short · 4
Conceptual analysis
A change in a system. Predict the effect and say why, with the right noun.
Short · 4
Model or visual
A diagram, phylogeny, or membrane. Read the figure before you write.
Short · 4
Data analysis
Chi-square, error bars, a rate. The formula sheet is in front of you. Use it.
Practice the because with Stephen AI, then handwrite a released set and score it yourself. The tutor is not the AP reader.
A review window to May.
During the year, lock each unit as you finish it. The last weeks are mixed practice, not a new textbook. The last ten days are timing and handwriting — no new content.
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During the course
One unit, then retrieve
When a unit closes, quiz it once from memory and keep a miss list. Do not wait until April to meet Unit 3.
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Last ~8 weeks
Weight 7, 3, and 6
Deepen the heavy units, then 4, 8, and 2. Light-touch 1 and 5. Start timed FRQs. That calendar is the same idea as how to use AI for exam prep: quiz, drill misses, then a mock with the chat closed.
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Last 10 days
Timed, mixed, on paper
One full 90-minute FRQ set handwritten. A Bluebook preview so the digital half is not a surprise. Sleep. Do not open a new chapter.
Your notes. Then a quiz.
Photograph the lecture. Answer from memory. Drill the misses. Stephen AI is the tutor on that page — not a stand-in for released FRQs. An AP Biology study guide that quizzes you from your notes.
AP Biology.
Straight answers.
How long is the AP Biology exam?
Three hours, split into two 90-minute halves that are each worth 50% of the score. Section I is 60 multiple-choice questions. Section II is six free-response questions. There is a short break between them. A calculator is allowed on both halves.
How many units are in AP Biology?
Eight, in the College Board Course and Exam Description: Chemistry of Life, Cells, Cellular Energetics, Cell Communication and Cell Cycle, Heredity, Gene Expression and Regulation, Natural Selection, and Ecology. Every unit appears on the exam. They are not weighted equally.
Which AP Biology unit is weighted the most?
Natural Selection (Unit 7) at 13–20% of the multiple-choice section. Cellular Energetics and Gene Expression and Regulation are next, each 12–16%. Those three can be close to half the MCQ. Units 1 and 5 are the lightest, at 8–11% each. None of them can be skipped.
Is a calculator allowed on the AP Biology exam?
Yes. A four-function calculator with square root, a scientific calculator, or a graphing calculator is allowed on both sections. You also get the official Equations and Formulas sheet. You do not need to memorize Hardy-Weinberg, chi-square, or water potential. You do need to know which formula the data is asking for.
How many FRQs are on the AP Biology exam?
Six in 90 minutes: two long questions worth 9 points each, and four short questions worth 4 points each. The long ones ask you to interpret experimental results, one of them with graphing. The shorts cover scientific investigation, conceptual analysis, a model or visual, and data analysis. Write in the paper booklet. Partial credit is the scoring system — answer every lettered part.
How do you get a 5 on AP Biology?
Weight review to Units 3, 6, and 7, then practice the skills the exam grades: reading a graph, designing or critiquing an experiment, and writing a causal sentence. Work released free-response questions from AP Central against the scoring guidelines. Handwrite them. Sit at least one timed mixed set before May. Rereading the chapter is the slow way to the same 2.
Is AP Biology hard?
It is hard if you treat it as a vocabulary test. College Board reported that in 2026 about 15% of students earned a 5 and about 71% earned a 3 or higher. The volume is real — eight units from molecules to ecosystems — but most missed points come from data, experimental design, and vague writing, not from forgetting a definition.
What is on the AP Biology formula sheet?
The Equations and Formulas sheet is printed for you and available in Bluebook. It includes Hardy-Weinberg, chi-square, water potential, rate, and population-growth models, among others. Practice finding the right equation under time. Do not spend January memorizing formulas that will be sitting in front of you in May.
Weight the units. Write the because.
The system you just read, on your notes. Download Stephen AI.