Edexcel IAL Biology Specification Checklist — Every Unit, With the Mark-Scheme Key Terms Highlighted
The complete Edexcel International A-Level Biology specification — Units 1 to 6 (WBI11–WBI16), every learning objective and all 18 core practicals — as one interactive revision checklist. The key terms examiners look for are highlighted the way you'd highlight them on paper. Tick each point as you master it: your progress is saved on this device.
How the six IAL Biology units fit together
AS (International Advanced Subsidiary) = Unit 1 (WBI11, Molecules, Diet, Transport and Health) + Unit 2 (WBI12, Cells, Development, Biodiversity and Conservation), each 1 h 30, 80 marks and 40% of AS, plus Unit 3 (WBI13, Practical Skills in Biology I), 1 h 20, 50 marks, 20% of AS.
A2 = Unit 4 (WBI14, Energy, Environment, Microbiology and Immunity) + Unit 5 (WBI15, Respiration, Internal Environment, Coordination and Gene Technology), plus Unit 6 (WBI16, Practical Skills in Biology II). AS and A2 each contribute 50% of the full International Advanced Level.
Exam sessions run in January, June and October, and single units can be resat to improve your UMS — so this checklist works whichever sitting you are targeting. Practical skills are examined in written papers (Units 3 and 6): the 18 core practicals badged below are exactly what those papers test.
Flip through the IAL Biology books
Real pages from the notes and solved past papers built on this exact specification — tap a cover to open it here.
AS Biology Notes
Every spec point in mark-scheme language
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Unit 1 Solved Past Papers
WBI11 answers, point by point
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Unit 2 Solved Past Papers
WBI12 answers, point by point
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Unit 3 Solved Past Papers
The practical paper, solved for the marks
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Every WBI11–WBI16 question since 2019, solved in the highlighted words
The complete Edexcel IAL Biology solved past papers, Units 1–6, 2019–2026 — every answer written point by point in the same mark-scheme key terms highlighted on this page, with new series added automatically.
Get the IAL Biology Solved Past Papers → See the IAL Biology NotesAbout the Edexcel IAL Biology specification (WBI11–WBI16)
The Pearson Edexcel International Advanced Level in Biology is a modular qualification: six units, each examined and graded separately, with sessions in January, June and October. Units 1–3 make up the International AS; Units 4–6 complete the full A-level. The specification (sometimes called the syllabus) lists every examinable idea as a numbered learning objective — 8 content topics across four theory units, plus 18 core practicals assessed in the two practical-skills papers — and that is exactly what this checklist tracks.
The pink highlights are not decoration: they are the key terms the mark schemes reward . Examiners award marks for precise vocabulary — water potential gradient , not "water concentration"; substrate level phosphorylation , not "making ATP". Learning each specification point together with its highlighted terms is the fastest route from a B to an A.
Use this page as your master tracker, then go deeper per topic with the detailed guides: Topic 1, Topic 2, Topic 3, Topic 4, Unit 3 practicals, Topic 5, Topic 6, Topic 7, Topic 8 and Unit 6 practicals.
Then close the loop: learn each unit in the IAL AS Biology course or IAL A2 Biology course, revise with Mr Hosni live in the IAL Biology live classes, and confirm every ticked point with the solved past papers (2019–2026).
Edexcel IAL Biology specification — FAQ
What are the unit codes for Edexcel IAL Biology?
WBI11 (Molecules, Diet, Transport and Health), WBI12 (Cells, Development, Biodiversity and Conservation), WBI13 (Practical Skills in Biology I), WBI14 (Energy, Environment, Microbiology and Immunity), WBI15 (Respiration, Internal Environment, Coordination and Gene Technology) and WBI16 (Practical Skills in Biology II). The AS cash-in is XBI11 and the full IAL cash-in is YBI11.
How is the IAL different from the UK A-level in Biology?
The IAL is modular: each unit is examined separately, sessions run in January, June and October, and individual units can be resat to improve UMS. The UK A-level is linear, with everything examined at the end. The IAL is the version taken by international schools.
Is there a separate practical exam?
Practical skills are assessed through written papers: Unit 3 (WBI13) at AS and Unit 6 (WBI16) at A2. They test the 18 core practicals badged CORE PRACTICAL in this checklist — methods, variables, reliability, validity, graphs and evaluation.
What do the pink highlights mean?
They are the key terms from the mark schemes. Examiners award marks for precise scientific vocabulary, so revising each specification point with its highlighted terms trains you to write answers the way marks are actually given.
Which exam sessions does this specification cover?
The current 2018 specification remains the examined version for the January, June and October sessions, including 2026 and 2027. Any single unit can be sat or resat in any session.
See how precise biological terms turn understanding into marks in Cambridge IGCSE and Edexcel International A Level Biology. The video shows how concise notes, highlighted key terms, flashcards and quizzes help you build stronger past-paper answers.
Turn this checklist into an A*
The complete IAL Biology system: video lessons in specification order, notes written in the highlighted mark-scheme language, 22 revision classes, quizzes and flashcards, every past paper solved, and direct WhatsApp support from Mr Hosni — the teacher of a Pearson Outstanding Learner Award winner.
IAL AS Biology Course → IAL A2 Biology Course Join Live IAL Biology Classes