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AP Biology · 8 units · 60 topics

Score a 5 on AP Biology.

Eight units covering molecular interactions, cells, energetics, information, evolution, and ecology.

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Study notes

Every AP Biology unit, explained.

Unit 1 is free to read in full. Every other unit shows its first topic free; a 7-day trial opens the rest.

  1. Unit 1Chemistry of Life7 topicsFreeRead unit
  2. Unit 2Cells10 topicsPreviewPreview
  3. Unit 3Cellular Energetics5 topicsPreviewPreview
  4. Unit 4Cell Communication and Cell Cycle6 topicsPreviewPreview
  5. Unit 5Heredity5 topicsPreviewPreview
  6. Unit 6Gene Expression and Regulation8 topicsPreviewPreview
  7. Unit 7Natural Selection12 topicsPreviewPreview
  8. Unit 8Ecology7 topicsPreviewPreview
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AP Biology · Sample questions

1

Researchers performed a bacterial transformation experiment in which they introduced a plasmid containing an ampicillin resistance gene into E. coli cells. After plating on ampicillin-containing medium, they observed colonies. Which of the following investigations would be most appropriate to determine whether the ampicillin resistance gene is being actively expressed?
FAQ

AP Biology questions, answered.

What's on the AP Biology Exam?
The AP Biology Exam is 3h long: Multiple choice (60 questions, 90 minutes, 50% of the score) and Free response (6 questions, 90 minutes, 50% of the score). These figures come from College Board's AP Biology exam page.
Are these AP Biology notes free?
Unit 1 is free to read in full, and every other unit shows its first topic free. A free 7-day trial opens all 8 units and the full-length practice tests.
How many units are in AP Biology?
AP Biology has 8 units: Unit 1, Chemistry of Life; Unit 2, Cells; Unit 3, Cellular Energetics; Unit 4, Cell Communication and Cell Cycle; Unit 5, Heredity; Unit 6, Gene Expression and Regulation; Unit 7, Natural Selection; Unit 8, Ecology.
When is the AP Biology Exam?
AP Exams are held over two weeks every May. College Board publishes the schedule for each year; the AP exam calendar lists the dates once they are announced.
How is the AP Biology Exam scored?
AP Exams are scored from 1 to 5. The AP Biology score calculator estimates your score from your results on each section.

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