Is A-Level Biology Hard? What 25 Years of Teaching Has Shown Me
An honest answer from someone who has taught it for over two decades, examined for two boards, and watched thousands of students go through it. Short version: yes, but probably not for the reasons you think.
The Honest Answer
I have been teaching A-Level Biology for over 25 years. I have examined for WJEC/Eduqas and Edexcel. I have watched students who were predicted A*s walk out of the exam in tears, and I have watched students who were predicted Ds pick up solid Bs because something finally clicked.
So when someone asks me whether A-Level Biology is hard, I cannot give a simple yes or no. What I can give you is this:
A-Level Biology is one of the most content-heavy A-Levels you can take. The sheer volume of material you need to learn is enormous. But content is not what makes it hard. What makes it hard is that knowing the content is not enough to get a good grade. You have to be able to apply it, analyse data you have never seen before, write precisely, and think on your feet in an exam hall.
That combination — large content volume plus demanding application skills — is what catches students out. Not the biology itself.
If you are reading this because you are deciding whether to take A-Level Biology, or because you have already started and you are finding it tough, the most important thing I can tell you is: it is hard, but it is entirely manageable with the right approach. The students who struggle are not the ones who lack ability. They are the ones who use the wrong strategies.
What the Numbers Say — 2025 Results
Let me show you the data, because it paints a clearer picture than anecdotes.
A-Level Biology is the third most popular A-Level in the UK, with over 65,000 entries in 2025. It is the most popular of the three sciences, ahead of Chemistry and Physics. That popularity is important context for what follows.
| Subject | A*–A % | A*–C % | Pass rate |
|---|---|---|---|
| Biology | 28.0% | 78.6% | ~97% |
| Chemistry | 32.0% | 80.3% | ~97% |
| Physics | 31.9% | 81.1% | ~97% |
| Maths | 41.3% | 82.5% | ~97% |
| All subjects | 28.2% | — | 97.4% |
Source: JCQ / Ofqual 2025 results, FFT Education Datalab. England data.
There are two things worth noticing here.
First, Biology has the lowest proportion of top grades (A*–A) of all three sciences — 28.0% compared to 32.0% in Chemistry and 31.9% in Physics. That is a meaningful gap, and it has been consistent for years.
Second, Biology’s top-grade rate is almost exactly the same as the all-subjects average (28.2%). That means Biology is harder than average to get an A or A* in, despite being a popular subject that attracts a broad range of students.
The Step Up from GCSE — Why Year 12 Hits Hard
I say this to every new Year 12 class at the start of term, and I will say it to you now: do not assume that because you did well at GCSE, A-Level Biology will come easily.
The step up is one of the biggest of any subject. Here is why.
At GCSE, Biology is largely about learning facts and reproducing them. You learn that enzymes are biological catalysts, that osmosis is the movement of water, that mitosis produces two identical cells. The exams test whether you remember these things. Most of it is recall.
At A-Level, the game changes completely. You are expected to understand mechanisms — not just what happens, but how and why it happens at a molecular level. You need to explain enzyme kinetics using the induced fit model. You need to describe osmosis in terms of water potential gradients. You need to know not just that mitosis produces identical cells, but every stage of the process, the role of each structure involved, and what happens when it goes wrong.
| GCSE level | A-Level level |
|---|---|
“Enzymes have an active site that the substrate fits into.” Sufficient at GCSE for full marks. | “The active site has a specific tertiary structure that is complementary to the substrate. On binding, the active site undergoes a conformational change (induced fit), lowering the activation energy of the reaction.” Required at A-Level. Precise terminology is essential. |
“The heart pumps blood around the body.” Fine at GCSE. | “The left ventricle generates high pressure to pump blood through the systemic circulation. The atrioventricular valves prevent backflow into the atria when ventricular pressure exceeds atrial pressure.” A-Level requires mechanism and causation. |
On top of this, the content volume roughly doubles. There are entirely new topics at A-Level that have no GCSE foundation — respiration biochemistry, the Calvin cycle, gene regulation, population genetics, and statistics. These topics hit students from scratch, with no prior knowledge to build on.
This is why many students who achieved 8s and 9s at GCSE find themselves getting Cs and Ds in their first Year 12 assessments. It is not a sign that they cannot do it. It is a sign that the approach that worked at GCSE — memorise, reproduce, repeat — does not work at A-Level.
The Topics That Cause the Most Problems
After 25 years and two exam boards’ worth of marking experience, I can tell you which topics students find hardest with a high degree of confidence. These are the areas where marks are most commonly lost, across all boards.
Respiration Biochemistry
The sheer number of steps, coenzymes (NAD, FAD, coenzyme A), and the chemiosmotic theory. Students routinely confuse where each stage occurs, what enters and leaves each stage, and how the electron transport chain generates ATP.
Photosynthesis
The two photosystems, the role of NADP, cyclic vs non-cyclic photophosphorylation, and then the Calvin cycle with its carbon fixation, reduction, and regeneration stages. Students confuse this constantly with respiration.
Gene Expression & Regulation
Abstract and conceptually demanding. Students can describe transcription and translation but struggle with how gene expression is controlled — particularly epigenetic mechanisms like DNA methylation and histone modification.
Statistics & Mathematical Skills
Around 10% of marks across all exam boards require mathematical skills. Many biology students chose the subject partly because they preferred it to maths-heavy sciences, so this catches people off guard.
Synoptic Questions
Particularly the AQA 25-mark essay and OCR’s Paper 3. These require you to pull together knowledge from across the entire specification, which students who revise topic-by-topic in isolation find extremely challenging.
If you are looking for revision support on these topics, I have free resources covering several of the core areas, and my one-to-one tuition is specifically designed to target the topics each student finds hardest.
Finding A-Level Biology Tough?
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Book Free ConsultationBiology vs Chemistry vs Physics — Which Is Hardest?
This is one of the most common questions I get from students choosing their A-Levels. The honest answer is that they are hard in different ways.
Physics is widely considered the most conceptually difficult. It requires strong mathematical ability, including calculus at the higher end, and the ability to work with abstract physical principles. Most students and teachers agree it is the hardest of the three sciences.
Chemistry sits in the middle. It demands a mix of mathematical reasoning (particularly in physical chemistry), pattern recognition (organic chemistry), and precise recall. Students who are strong in both maths and logical thinking tend to do well.
Biology has less maths than either Chemistry or Physics, but compensates with a significantly larger content volume and a greater emphasis on written communication. The questions require you to write precisely and at length — something that Physics and Chemistry exams demand less of.
The grade data supports this picture. In 2025, 41.3% of Maths students achieved A*–A, compared to 32.0% in Chemistry, 31.9% in Physics, and just 28.0% in Biology. But this does not mean Biology is the “hardest” in absolute terms — it reflects the different student populations taking each subject.
Why the Exams Are Harder Than the Content
This is something I wish every student understood before they sat their first A-Level Biology exam.
You can know all the biology and still do badly. I have seen it happen hundreds of times. I have marked it happen hundreds of times.
The reason is that A-Level Biology exams do not just test whether you know things. They test whether you can:
- Apply knowledge to unfamiliar contexts — you will be given data, experiments, or scenarios you have never seen and asked to explain them using biological principles
- Interpret and analyse data — graphs, tables, statistical outputs, experimental results, all requiring you to draw conclusions and evaluate methodology
- Write with precision — mark schemes are specific. “The enzyme changes shape” might earn zero marks if the mark scheme requires “the tertiary structure of the enzyme is altered so the active site is no longer complementary to the substrate”
- Follow command words exactly — “Describe” and “Explain” require fundamentally different answers, and students routinely lose marks by answering one when the question asks for the other
As an examiner, I can tell you that the single most common reason students underperform is vague language. They know the biology but cannot express it in the precise way that earns marks. This is a skill that can be taught and practised — and it is the main thing I focus on in my tuition sessions.
For a detailed guide on how to structure exam answers, see my article on how to get an A* in A-Level Biology.
What Makes the Difference Between Struggling and Succeeding
In 25 years of teaching, I have seen students with every starting point — from predicted A*s who fell apart, to predicted Ds who pulled out Bs. The pattern is remarkably consistent. The students who succeed are the ones who:
Start early and stay consistent. Biology rewards steady, daily work over cramming. The volume of content makes it nearly impossible to catch up if you fall behind. Thirty minutes a day, every day, is worth far more than a six-hour weekend session once a fortnight.
Use active revision methods. Re-reading notes is the single least effective revision strategy, yet it is the one most students default to. Flashcards, self-testing, past paper questions, and teaching concepts to someone else are all dramatically more effective. I go into detail on this in my A* guide.
Practise exam technique separately from content revision. Knowing the biology and being able to write it in a way that earns marks are two different skills. Practising past paper questions and marking them honestly against the mark scheme is the fastest way to improve your grade.
Ask for help early. Students who struggle in silence until March and then panic are far harder to help than students who flag problems in October. Talk to your teacher. Consider a tutor. Use resources. The earlier you address a problem, the easier it is to fix.
Do not rely on memorisation alone. Understand the why behind every process. If you can explain a mechanism to someone who knows nothing about biology, you understand it. If you can only repeat what your notes say, you have memorised it — and that will not be enough.
Does the Exam Board Matter?
Students often ask whether some boards are harder than others. The short answer is no — Ofqual ensures comparable outcomes across all boards. But the exam style differs significantly, and that matters.
AQA has no multiple choice and includes a unique 25-mark synoptic essay. If you struggle with extended writing, this is challenging. If you are a strong writer, it is an opportunity.
Edexcel A (Salters-Nuffield) uses a pre-released article for Paper 3, requiring analytical and application skills. The context-based approach suits students who like applying biology to real-world scenarios.
OCR A tests application to unfamiliar contexts more heavily than other boards. If you are good at thinking on your feet, this works in your favour.
WJEC/Eduqas offers optional topics and (for WJEC) a unitised structure. Having examined for this board, I can tell you the QER (Quality of Extended Response) questions require a particularly structured, logical approach.
For a full breakdown, see my comprehensive exam board comparison.
The Bottom Line
A-Level Biology is hard. The content is vast, the exams are demanding, and the precision required catches many students off guard. But it is not impossible, and it is not even close to impossible for students who approach it the right way.
The students I have seen succeed — and I have seen a lot of them over 25 years — are not the ones with the highest natural ability. They are the ones who work consistently, revise actively, practise exam technique, and are honest about their weaknesses.
If you are finding A-Level Biology difficult, you are not alone. The data shows that most students find it challenging. But with the right support and the right methods, it is entirely achievable. If you want expert guidance from someone who has sat on the other side of the mark scheme, I offer one-to-one tuition and group sessions covering all exam boards.
Frequently Asked Questions
Yes — significantly. The content volume roughly doubles, the depth of understanding required increases dramatically, and the exam style shifts from largely recall-based to application and analysis. Many students who achieved high grades at GCSE find the first term genuinely challenging. The students who adapt quickest are those who move from memorising facts to understanding mechanisms and processes.
They are difficult in different ways. Chemistry requires stronger mathematical and abstract thinking skills. Biology has significantly more content and requires greater precision in written answers. In 2025, 28.0% of Biology students achieved A*–A compared to 32.0% in Chemistry, suggesting Biology is statistically harder to achieve top grades in — though this partly reflects the wider range of students who take Biology.
Most schools and colleges require a minimum of grade 6 (formerly B) in GCSE Biology or Combined Science. Some competitive sixth forms ask for grade 7 or above. A strong GCSE Maths grade is also beneficial, as around 10% of A-Level Biology marks require mathematical skills.
The topics students most commonly struggle with are: respiration biochemistry (Krebs cycle, oxidative phosphorylation), photosynthesis (Calvin cycle, light-dependent reactions), gene expression and regulation (transcription factors, epigenetics), statistics (chi-squared, Hardy-Weinberg), and synoptic questions that link concepts across multiple topic areas.
No — this is one of the biggest misconceptions. While there is a large volume of content to learn, memorisation alone will not get you above a B. Modern A-Level Biology exams heavily test application of knowledge to unfamiliar contexts, data analysis, experimental evaluation, and extended writing. Students who develop genuine understanding consistently outperform those who rely on memorisation.
Aim for 4–5 hours of independent study per week during Year 12, increasing to 6–8 hours during Year 13, plus more in the final weeks before exams. Consistency matters more than volume — regular shorter sessions beat occasional long cramming sessions every time. Focus on active methods like past papers and self-testing rather than passive re-reading.
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Disclaimer: The information provided on this page is intended for educational guidance only. While every effort has been made to ensure accuracy, Biology Education and its author accept no responsibility for individual exam outcomes. Grade data is sourced from JCQ, Ofqual, and FFT Education Datalab (2025). Students are advised to consult their own teachers, tutors, and official exam board resources.