Edexcel International A Level Biology — Revision Notes & Past Papers
Free Pearson Edexcel International A Level Biology (XBI11 IAS / YBI11 IAL) revision notes, worked examples, AI-marked practice and past papers — mapped to the full unit-based syllabus for the 2026 exam cohort.
What is Edexcel International A Level Biology?
What is Edexcel International A Level Biology?
Pearson Edexcel International A Level Biology (XBI11 IAS / YBI11 IAL) is a modular, unit-based science qualification for international centres, with 100% external assessment and no coursework. The IAS covers Units 1-3 and the full IAL covers Units 1-6, spanning molecules, diet and transport, cells and biodiversity, energy and the environment, respiration and coordination, plus dedicated practical-skills units (Units 3 and 6) that assess experimental technique through written examinations.
Assessment
| Paper | Total marks | Duration | Style of questions |
|---|---|---|---|
| Unit 1 | 80 marks | 1h 30 | Written exam — Molecules, Diet, Transport and Health |
| Unit 2 | 80 marks | 1h 30 | Written exam — Cells, Development, Biodiversity and Conservation |
| Unit 3 | 50 marks | 1h 20 | Written exam — Practical Skills in Biology I |
| Unit 4 | 90 marks | 1h 45 | Written exam — Energy, Environment, Microbiology and Immunity |
| Unit 5 | 90 marks | 1h 45 | Written exam — Respiration, Internal Environment, Coordination and Gene Technology |
| Unit 6 | 50 marks | 1h 20 | Written exam — Practical Skills in Biology II |
IAS (XBI11) = Units 1-3; full IAL (YBI11) = Units 1-6. Units 1, 2, 4 and 5 are theory papers; Units 3 and 6 assess practical skills by written exam. 100% external; no coursework. IAS graded a-e; IAL graded A*-E.
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Access Edexcel International A Levels resources, videos, MCQ and structured practice questions, plus quizzes with AI-powered detailed reports — all designed to make your revision simple, focused, and effective
AS Level - Unit 1
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AS Level - Unit 2
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A Level - Unit 4
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A Level - Unit 5
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