Advanced Higher Biology: the shorter 2027 exam, the project and practice questions

The Advanced Higher Biology exam in 2027

That's 122 marks in all, with the exam worth 70% and the project 30% (it was 75% and 25%). The figures are from the course specification valid from session 2026 to 2027, and the date is from the 2027 timetable. Section 2 lost 15 marks and the paper lost 30 minutes after a survey of learners and teachers. The content is unchanged. The course is worth 32 SCQF credit points.

The project: you plan and carry out your own investigation and write it up as a report, and the specification expects at least 15 hours of experimental research. With the project now worth 30%, it's worth starting early.

What Advanced Higher Biology covers

• Cells and proteins: laboratory techniques, proteins, membrane proteins, communication and signalling, and protein control of cell division.
• Organisms and evolution: field techniques, evolution, variation and sexual reproduction, sex and behaviour, and parasitism.
• Investigative biology: scientific principles and process, experimentation, and reporting and critically evaluating research.

Advanced Higher Biology grade boundaries

In 2026, on the old format, out of 160 (the 100-mark paper scaled to 120, plus the project scaled to 40), an A needed 98, a B 83, a C 69 and a D 54. Of the 3,109 candidates, 19.7% got an A (course report 2026). The 2027 total is 122, so those numbers won't carry over. As a guide, the grading system aims for a C at about 50% and an A at about 70%.

Advanced Higher Biology practice questions

We wrote these for this guide. Many marks at this level are for applying what you know to unfamiliar data, so practise that as well as recall.

1. Laboratory techniques: linear dilution

Question: how would you make 20 cm³ of 0.25 mol l⁻¹ glucose from a 1.0 mol l⁻¹ stock? Answer: the concentration falls by a factor of 4, so a quarter of the volume is stock: 20 × 0.25 ÷ 1.0 = 5 cm³ of stock, made up with 15 cm³ of water. A serial dilution instead dilutes by the same factor at each step, such as tenfold.

2. Field techniques: mark and recapture

Question: 40 voles are marked and released. Later, 50 are caught, and 8 of them carry marks. Estimate the population. Answer: N = (number marked × number in second sample) ÷ number recaptured = 40 × 50 ÷ 8 = 250 voles. The estimate assumes the marks don't affect survival and the marked animals mix fully back in.

3. Membrane proteins

Question: explain how an integral protein is held in the plasma membrane. Answer: regions of the protein with hydrophobic R groups interact with the hydrophobic interior of the phospholipid bilayer, holding the protein in place. The 2026 report found only a few candidates described these hydrophobic interactions.

4. Experimentation: controls

Question: what is the purpose of a negative control? Answer: it's set up so no result is expected, for example boiled enzyme in place of active enzyme. If it shows no change, the results in the experiment can be put down to the independent variable.

5. Variation and sexual reproduction

Question: sexual reproduction is costly, as only half the population can bear young. Why has it persisted? Answer: it produces genetic variation, which lets populations adapt. The Red Queen hypothesis says hosts and parasites are locked in an arms race, and variation helps hosts keep pace with fast-evolving parasites. Test whether you can tell mitosis from meiosis in our Genetics and DNA course and press Mark.

Common Advanced Higher Biology mistakes

From the 2026 course report:

• Unfamiliar contexts: many candidates struggled to apply their knowledge to new situations.
• Recall of exact terms from the mandatory knowledge, when a single term or phrase was asked for.
• Investigative biology and data: weak conclusions from tables and graphs, and comparisons that weren't stated clearly.
• Box plots: some treated the range bar as if it were an error bar.
• Unclear writing that cost marks. Be concise and specific.

Use a daily paper as a short timed prelim

Today's Advanced Higher Biology paper is written at this level, but it doesn't follow the Scottish course closely. It touches on evolution, the Hardy-Weinberg principle, populations and nerve signalling, but much of it, such as photosynthesis and respiration in detail, the kidney, muscle contraction and gene technology, isn't in Advanced Higher Biology. It doesn't cover laboratory and field techniques, membrane proteins, parasitism or investigative biology. Treat it as extra practice at the level, and use the official past papers for the course itself, remembering that papers before 2027 are longer. For prelim dates, see our prelims guide.

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