UniGeniusAP Biology

AP Biology

AP Biology study planner for May 2027

Units are not worth the same. Natural Selection is 13–20% of Section I and Chemistry of Life 8–11%. Tell the planner how sure you are of each unit and it spends your hours where the points are.

Hours a week for AP Biology
Unit 1: Chemistry of Life 8–11%
Unit 2: Cells 10–13%
Unit 3: Cellular Energetics 12–16%
Unit 4: Cell Communication and Cell Cycle 10–15%
Unit 5: Heredity 8–11%
Unit 6: Gene Expression and Regulation 12–16%
Unit 7: Natural Selection 13–20%
Unit 8: Ecology 10–15%

28 weeks to the exam on May 3, 2027

Start with Unit 7

Natural Selection: 17.2 of your 112 hours. It carries 13–20% of Section I, about 10 of the 60 questions.

Hours per unit
UnitHoursAbout this many questions
Unit 7: Natural Selection17.210 of 60
Unit 3: Cellular Energetics14.68 of 60
Unit 6: Gene Expression and Regulation14.68 of 60
Unit 4: Cell Communication and Cell Cycle138 of 60
Unit 8: Ecology138 of 60
Unit 2: Cells127 of 60
Unit 1: Chemistry of Life9.96 of 60
Unit 5: Heredity9.96 of 60

Week by week

  1. Week 1 · Oct 13Unit 7: Natural Selection
  2. Week 2 · Oct 20Unit 7: Natural Selection
  3. Week 3 · Oct 27Unit 7: Natural Selection
  4. Week 4 · Nov 3Unit 7: Natural Selection
  5. Week 5 · Nov 10Unit 7: Natural Selection, Unit 3: Cellular Energetics
  6. Week 6 · Nov 17Unit 3: Cellular Energetics
  7. Week 7 · Nov 24Unit 3: Cellular Energetics
  8. Week 8 · Dec 1Unit 3: Cellular Energetics, Unit 6: Gene Expression and Regulation
  9. Week 9 · Dec 8Unit 6: Gene Expression and Regulation
  10. Week 10 · Dec 15Unit 6: Gene Expression and Regulation
  11. Week 11 · Dec 22Unit 6: Gene Expression and Regulation
  12. Week 12 · Dec 29Unit 6: Gene Expression and Regulation, Unit 4: Cell Communication and Cell Cycle
  13. Week 13 · Jan 5Unit 4: Cell Communication and Cell Cycle
  14. Week 14 · Jan 12Unit 4: Cell Communication and Cell Cycle
  15. Week 15 · Jan 19Unit 4: Cell Communication and Cell Cycle, Unit 8: Ecology
  16. Week 16 · Jan 26Unit 8: Ecology
  17. Week 17 · Feb 2Unit 8: Ecology
  18. Week 18 · Feb 9Unit 8: Ecology
  19. Week 19 · Feb 16Unit 8: Ecology, Unit 2: Cells
  20. Week 20 · Feb 23Unit 2: Cells
  21. Week 21 · Mar 2Unit 2: Cells
  22. Week 22 · Mar 9Unit 2: Cells, Unit 1: Chemistry of Life
  23. Week 23 · Mar 16Unit 1: Chemistry of Life
  24. Week 24 · Mar 23Unit 1: Chemistry of Life, Unit 5: Heredity
  25. Week 25 · Mar 30Unit 5: Heredity
  26. Week 26 · Apr 6Unit 5: Heredity
  27. Week 27 · Apr 13Timed practice exam, then review every miss
  28. Week 28 · Apr 20Timed practice exam, then review every miss

Check your units with the free test

ExamMonday, May 3, 2027
Heaviest unitUnit 7, Natural Selection: 13–20%
Lightest unitsUnits 1 and 5: 8–11% each
Last weeksKept for timed practice exams

How the plan is made

  • Each unit starts from the middle of its published Section I weight range.
  • A unit you have not started gets about one and a half times its share; a solid unit gets under half.
  • Units are ordered heaviest need first, and the final one or two weeks are timed practice exams with review of every miss.

Making the hours count

  • Start each unit with a few questions to find what you do not know, then the lesson, then more questions.
  • Practice free-response answers every week: they are half the score.
  • Redo the plan when a unit moves from shaky to solid.

Try 2 questions

Question 1
Percent of town mosquitoes killed by a standard lab dose of insecticide after years of spraying.
Years of sprayingPercent killed by standard dose
095
288
472
651
834
1022
An insecticide was sprayed on a town's mosquitoes every summer. Each year, mosquitoes from the town were exposed to the same dose in the lab. Which statement best describes the data?
Question 2
A herbicide blocks the transfer of electrons from photosystem II to the electron transport chain in the thylakoid membrane. Which prediction is best supported?

Next step

Take the free diagnosticTake the course tour

College Board's AP Biology course page, with the unit weights

Questions people ask

Which AP Biology unit is weighted most?

Unit 7, Natural Selection, at 13–20% of the multiple-choice section, then Units 3 and 6 at 12–16% each.

How long should I study for AP Biology?

It depends on how much of the course you know. The planner turns your weekly hours into hours per unit; most students do best with steady weekly practice rather than a final cram.

When should I start studying for the 2027 AP Biology exam?

Now is best: steady weekly study through the school year leaves the final weeks for full practice exams before May 3, 2027.