Edexcel IAL Biology Past Papers & Mark Schemes (YBI11) – Updated 2026
Updated: Sep 7
Download Edexcel International A Level (IAL) Biology past papers, official mark schemes, and examiner tips for Units 1–6 (WBI11–WBI16).
Past Papers
Download IAL Biology past papers and mark schemes to practice effectively
Edexcel IAL Biology June 2026 Past Papers & Mark Schemes
2026 Edexcel IAL Biology (June) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 1A: Molecules, Diet, Transport & Health (WBI11/01A) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 2A: Cells, Development, Biodiversity & Conservation (WBI12/01A) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 3A: Practical Skills in Biology I (WBI13/01A) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 4A: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 5A: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01A) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Unit 6A: Practical Skills in Biology II (WBI16/01A) | ||
Edexcel IAL Biology January 2026 Past Papers & Mark Schemes
2026 Edexcel IAL Biology (January) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Edexcel IAL Biology October 2025 Past Papers & Mark Schemes
2025 Edexcel IAL Biology (October) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Edexcel IAL Biology June 2025 Past Papers & Mark Schemes
2025 Edexcel IAL Biology (June) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Edexcel IAL Biology January 2025 Past Papers & Mark Schemes
2025 Edexcel IAL Biology (January) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Edexcel IAL Biology October 2024 Past Papers & Mark Schemes
2024 Edexcel IAL Biology (October) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Edexcel IAL Biology June 2024 Past Papers & Mark Schemes
2024 Edexcel IAL Biology (June) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Edexcel IAL Biology January 2024 Past Papers & Mark Schemes
2024 Edexcel IAL Biology (January) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Edexcel IAL Biology October 2023 Past Papers & Mark Schemes
2023 Edexcel IAL Biology (October) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Edexcel IAL Biology June 2023 Past Papers & Mark Schemes
2023 Edexcel IAL Biology (June) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Edexcel IAL Biology June 2022 Past Papers & Mark Schemes
2022 Edexcel IAL Biology (June) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Edexcel IAL Biology November 2021 Past Papers & Mark Schemes
2021 Edexcel IAL Biology (November) | Downloads | |
Unit 1: Molecules, Diet, Transport & Health (WBI11/01) | ||
Unit 2: Cells, Development, Biodiversity & Conservation (WBI12/01) | ||
Unit 3: Practical Skills in Biology I (WBI13/01) | ||
Unit 4: Energy, Environment, Microbiology & Immunity (WBI14/01) | ||
Unit 5: Respiration, Internal Environment, Coordination & Gene Technology (WBI15/01) | ||
Unit 6: Practical Skills in Biology II (WBI16/01) | ||
Tip 1: Misinterpreting Command Words
This is the single most preventable source of lost marks in any biology exam. The command word tells you exactly what the examiner wants — ignore it and you can write a perfectly good answer to the wrong question.
If the word is "explain", scientific reasoning is required. Don't just describe what happens — say why it happens. Use connective language: because, therefore, as a result, so. These words signal to the examiner that you're making a causal link, not just narrating. If the word is "describe", do the opposite — state the trend or pattern you observe, without drifting into biological explanation. If a question asks you to "compare and contrast", you must address both similarities and differences explicitly — covering only one side will not access full marks. And if you see "determine", that's the examiner's way of telling you a calculation is required.
Underline the command word before you write anything. Make it a habit.
Tip 2: Significant Figures and Rounding
This is a small technical detail that costs marks with surprising regularity — and there's really no excuse for it once you know what to look for.
If the question specifies a number of significant figures or decimal places, follow it exactly. If it doesn't, look at the values already given in the question or data table and match their precision — that's your guide. Most importantly, show every step of your working. Even if your final answer is incorrectly rounded, method marks are available for correct working throughout. A right method with a rounding slip at the end is far better than a bare answer with no working shown at all.
Tip 3: Formatting Ratios Incorrectly
This is a simple presentation error that loses marks unnecessarily — the biology might be completely right, but if the ratio isn't expressed correctly, the mark isn't awarded.
A ratio should be written in the form x : 1 or 1 : x. To get there, divide both values by the smaller one so that one side cancels down to 1. For example, if your raw numbers are 18 and 6, divide both by 6 to give 3 : 1. Don't just write the result of a single division — that's not a ratio, that's just a number. The colon and both values must be present.
Tip 4: Confusing "Alleles" and "Genes"
In everyday conversation these words get used interchangeably — in A-level biology, they absolutely cannot be.
A gene is a specific locus on a chromosome — a fixed location that codes for a particular protein or characteristic. An allele is a specific version of that gene. When you're discussing inheritance, mutations, or sex-linked conditions, you are almost always talking about a particular allele, not the gene itself. Saying "the haemophilia gene is carried on the X chromosome" is imprecise — what you mean is "the haemophilia allele is located on the X chromosome." Examiners will penalise the substitution, so get the habit right now.
Tip 5: Giving Genotypes Without Phenotypes
This is one of the most common ways to drop the final mark in a genetics question. The genotype work is all correct — and then the phenotype is simply never stated.
Whenever you write a genotype in a genetic cross or pedigree analysis, explicitly state what that genotype means in terms of the physical characteristic. Don't assume it's obvious. Write it out: "Pp — unaffected carrier," "pp — affected individual." The examiner needs to see that you can connect the notation to the biology. Those final descriptor marks are easy marks — but only if you actually write the phenotype down.
Tip 6: Careless Diagram Drawing and Labelling
Diagrams feel like easy marks — and they are, but only if you treat them with the same precision you'd give a written answer.
Label lines must touch the exact structure being identified — not approximately near it, not pointing vaguely in its direction. If the line doesn't land on the right structure, the mark isn't awarded. When drawing molecules, apply basic chemical rules: carbon forms four covalent bonds, always — an incorrectly bonded carbon tells the examiner your understanding is shaky. If the question provides a specific drawing style or convention, replicate it exactly rather than improvising your own. A neat, precise diagram drawn slowly is worth far more than a quick sketch.
Tip 7: Repeating the Question Back to the Examiner
Rewriting information from the question stem takes up time, uses up lines, and gains absolutely zero marks. The examiner already knows what they wrote.
Instead, use the stem as a signpost. The information given is a hint pointing you toward the relevant specification topic — your job is to pick it up and develop it with your own biological knowledge. If the question says "use the information in the table," that means manipulate the data, calculate something, or use a figure to support a scientific point. Simply restating the numbers in a different sentence is not using the data — and it won't be credited.
Tip 8: Getting Hydrogen Bonds in Protein Structure Wrong
This mistake is very specific and very common: hydrogen bonds in the secondary structure do not form between R groups.
Be precise about location at every level. In the secondary structure — alpha helices and beta-pleated sheets — hydrogen bonds form between the amino and carboxyl groups of the polypeptide backbone. The R groups are not involved at this level at all. It is only at the tertiary and quaternary levels that R groups become relevant, where they participate in hydrogen bonds, ionic bonds, and disulfide bridges depending on their chemistry. State the distinction clearly and explicitly — vague answers about "bonds between parts of the protein" will not access the mark.
Is the Edexcel IAL Biology syllabus changing for 2027?
As of May 2026, no — Pearson Edexcel has made no official announcement of a new IAL Biology specification for 2027. The current 2018 specification (first assessed in 2019) remains fully active.
Current Status at a Glance
Feature | Status for 2027 |
Active Specification | Biology 2018 (Issue 2) |
Assessment Structure | Modular — Units 1–3 (AS Level), Units 4–6 (Full A Level) |
Exam Windows | January, June, and October — unchanged |
What to Keep an Eye On
No major overhaul is planned, but two things are worth monitoring:
Teaching Science Newsletters — Pearson publishes these periodically (most recently May 2026). They typically cover minor mark scheme tweaks or administrative updates, not full syllabus rewrites.
Provisional Timetables — June 2027 timetables are already being circulated to centres and currently align with the existing modular structure.
A Note on CAIE vs. Edexcel
Cambridge (CAIE) updated their A Level Biology syllabus (9700) for the 2025–2027 cycle, but Edexcel has not made a corresponding change to the IAL. If you're working across both boards, don't assume updates to one apply to the other.
Tip: Continue using the 2018 Specification (Issue 2) until an official Notice to Centres states otherwise. If a new spec were planned for 2027 first teaching, Pearson would typically announce it at least 12 months in advance — and no such notice has been issued.
When are the Edexcel IAL Biology exams scheduled for late 2026 and 2027?
October 2026 Series (Confirmed)
Unit | Title | Session |
Unit 1 | Molecules, Diet, Transport and Health | Afternoon |
Unit 2 | Cells, Development, Biodiversity & Conservation | Morning |
Unit 3 | Practical Skills in Biology I | Morning |
Unit 4 | Energy, Environment, Microbiology & Immunity | Morning |
Unit 5 | Respiration, Internal Env, Coordination & Gene Tech | Morning |
Unit 6 | Practical Skills in Biology II | Morning |
Exact day-by-day dates are confirmed in the Final Timetable — check the Pearson Support portal in late Summer 2026.
January 2027 Series (Confirmed)
Unit | Date | Session |
Unit 1 (WBI11) | Friday, 8 January | Morning |
Unit 2 (WBI12) | Tuesday, 12 January | Morning |
Unit 3 (WBI13) | Thursday, 14 January | Morning |
Unit 4 (WBI14) | Monday, 18 January | Morning |
Unit 5 (WBI15) | Wednesday, 20 January | Morning |
Unit 6 (WBI16) | Friday, 22 January | Morning |
Summer 2027 Series (Provisional)
Unit | Date | Session |
Unit 1 (WBI11) | Tuesday, 4 May | Afternoon |
Unit 2 (WBI12) | Friday, 14 May | Afternoon |
Unit 3 (WBI13) | Thursday, 20 May | Afternoon |
Unit 4 (WBI14) | Monday, 24 May | Afternoon |
Unit 5 (WBI15) | Monday, 7 June | Afternoon |
Unit 6 (WBI16) | Friday, 11 June | Afternoon |
Summer 2027 dates are provisional and subject to finalisation. Confirm via the Pearson Edexcel timetable portal closer to the series.
How much harder is Edexcel IAL Biology compared to IGCSE Biology?
The jump is real, but manageable — especially given IAL's modular structure. The core shift is the same as in other A Level sciences: IGCSE teaches you what happens; IAL requires you to explain exactly how and why it happens, usually at a molecular level.
What Actually Changes
Feature | IGCSE / O Level Biology | Edexcel IAL Biology |
Focus | General principles and foundations | Detailed molecular and physiological mechanisms |
Maths | Basic percentages and simple graphs | Statistical tests, rates of reaction, unit conversions |
Practical Skills | Describing simple experiments | Planning complex investigations with controlled variables (Units 3 & 6) |
Question Style | Direct and predictable | Context-heavy; requires linking across the syllabus |
Three Things That Catch Students Off Guard
1. Content Volume
The IAL syllabus is roughly 3–4 times larger in terms of facts and definitions compared to IGCSE. At IGCSE you learn that enzymes break down food; at IAL Unit 1 you must explain the precise 3D tertiary structure, the specific hydrogen and ionic bonds at the active site, and the induced fit mechanism of catalysis.
2. The Edexcel Mark Scheme
This is the most common shock for students transitioning from IGCSE. You can understand a concept perfectly and still score zero if you don't use the exact keywords the mark scheme requires. Extended response questions (worth up to 6 marks) also demand a logical, structured flow that IGCSE rarely asks for.
3. Application Over Recall
IGCSE rewards memorisation. IAL rewards the ability to apply knowledge to unseen scenarios — you might be given a graph about an obscure deep-sea organism and asked to explain its gas exchange mechanisms using first principles. Data analysis also steps up significantly, with questions requiring standard deviation calculations and statistical tests like the t-test and Chi-squared.
The Modular Advantage
Unlike linear O Level or IGCSE (where everything is examined at once), IAL lets you focus on one unit at a time — for example, sitting only Unit 1 in October before moving on. This makes the workload considerably more manageable.
Tip: Start practising Unit 1 past papers early in your preparation. You'll quickly find the challenge isn't the biology itself — it's learning to answer the way Edexcel expects.
