Advanced Higher Biology
From session 2026/27, Advanced Higher Biology has an 85-mark exam lasting 2 hours 30 minutes. The project is worth 30% of the grade. The 2027 exam is on Wednesday 12 May, 9:00 to 11:30.
- Question paper09:00 to 11:30
What grade is my mark?
Type a total mark to see the grade it would have got.
How the A and C boundaries have moved
Boundaries as a share of the total marks. A lower line means the papers were judged harder that year. Qualifications Scotland publishes boundaries from 2022 in this format.
| Year | Out of | A | B | C | D |
|---|---|---|---|---|---|
| 2026 | 160 | 98 | 83 | 69 | 54 |
| 2025 | 160 | 100 | 84 | 69 | 53 |
| 2024 | 160 | 104 | 87 | 70 | 53 |
| 2023 | 120 | 82 | 66 | 51 | 35 |
| 2022 | 120 | 72 | 58 | 44 | 30 |
What changed for 2026/27
The question paper was cut from 100 marks to 85, and from 3 hours to 2 hours 30 minutes. Section 1 keeps 20 multiple choice marks. Section 2 has 65 marks.
Scaling no longer applies to the question paper. The project still has 30 marks but now counts for 30% of the grade, up from 25%. It is scaled to 37, giving a course total of 122.
The project
The project is an individual investigation that you plan and carry out. The course specification expects at least 15 hours of experimental research. The report must be 3,000 to 3,600 words, not counting tables, graphs, references and appendices. A penalty applies if it runs more than 10% over the maximum.
With the project now worth almost a third of the grade, the discussion section matters more than ever. That is where the 2025 report found the most lost marks.
Course content
Cells and proteins covers lab techniques, proteomics, membrane proteins, cell signalling and the control of cell division. Organisms and evolution covers field techniques, evolution, reproduction, behaviour and parasitism. Investigative biology covers research methods and evaluating published science.
Investigative biology questions often describe a study and ask you to judge its design. Expect questions on controls, replicates, sampling and bias. The same skills earn marks in the project discussion.
Examiner feedback from 2025
Candidates did best on questions asking for terms or straightforward statements. Extended-response answers were often strong. Questions on the sodium-potassium pump, Hardy-Weinberg and r and K selection went well.
Weaker areas were:
- applying knowledge to new or unfamiliar contexts
- investigative biology questions
- drawing conclusions from tables and graphs
- interpreting phylogenetic trees
- telling qualitative data from quantitative data
- unit conversions that threw off final answers
In projects, procedures and results were usually well described. The discussion was weaker, with thin evaluation and limited critical analysis.
The report asked centres to focus on applying knowledge rather than recall. It also asked for projects of suitable complexity, with a range of topics within each class.
Preparing with past papers
Older papers had 100 marks over 3 hours. They remain useful, but practise finishing them faster. Spend extra time on data-handling questions and check every unit conversion before the final answer.
Revision checklist
Tick topics as you revise. Ticks are saved on this device only.
- Plan your project so you can complete at least 15 hours of experimental work.
- Write the project discussion first in draft, then evaluate every source of error.
- Keep the project report between 3,000 and 3,600 words.
- Practise reading phylogenetic trees and stating what they show about relatedness.
- Work Hardy-Weinberg calculations from both genotype and phenotype data.
- Classify data as qualitative or quantitative, and explain why.
- Practise unit conversions such as mM to M and micrometres to millimetres.
- Answer data questions by writing a conclusion that quotes figures from the table or graph.
- Explain membrane transport proteins, including the sodium-potassium pump, step by step.
- Answer one unfamiliar-context question a day from any recent past paper.
Quick answers
- How long is the Advanced Higher Biology exam in 2027?
2 hours 30 minutes. That is 30 minutes shorter than before, and the paper now has 85 marks.
- How much is the Advanced Higher Biology project worth?
30% of the grade. It is marked out of 30 and scaled to 37.
- What is the project word count?
3,000 to 3,600 words, excluding tables, graphs, references and appendices.
- When is the Advanced Higher Biology exam in 2027?
Wednesday 12 May 2027, 9:00 to 11:30.