National 5 Biology
National 5 Biology is now a 2-hour exam worth 80 marks plus a 20-mark assignment. The 2027 exam is on Wednesday 12 May, 13:00 to 15:00.
- Question paper13:00 to 15:00
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 | 125 | 86 | 74 | 62 | 50 |
| 2025 | 125 | 86 | 74 | 62 | 50 |
| 2024 | 125 | 86 | 72 | 58 | 44 |
| 2023 | 100 | 77 | 65 | 53 | 41 |
| 2022 | 100 | 61 | 49 | 37 | 25 |
The 2026/27 changes
Qualifications Scotland cut the Biology question paper for this session. It is now 80 marks in 2 hours, down from 100 marks in 2 hours 30 minutes. Section 1 has 20 multiple choice marks and Section 2 has 60.
Scaling has been removed from the 20-mark assignment. The split is now 80% exam, 20% assignment. The course content is unchanged.
Course content
The course has three areas. Cell biology covers cells, membranes, DNA, proteins, genetic engineering and respiration. Multicellular organisms covers cell division, the nervous and hormonal systems, reproduction, inheritance and transport. Life on Earth covers ecosystems, sampling, photosynthesis, food production and evolution.
The course specification also lists apparatus and techniques you must know. Examples include a respirometer and a potometer. Exam questions often describe these experiments.
The assignment
You research a topic, collect your own data and find data from a source. You then write the report under supervision in up to 1 hour 30 minutes. The whole task takes about 8 hours.
The 2025 report advised a single, clear aim rather than several. Teachers are asked to check that an investigation is workable before it starts.
Weak spots in the 2025 exam
Numerical skills improved, with good work on percentages and averages. Most candidates read an optimum pH from a graph and predicted phenotype chances in genetics.
Weaker answers came up in these areas:
- predicting mass changes in osmosis experiments with potato cylinders
- naming mitosis stages, especially the one before the cytoplasm divides
- naming active transport and explaining diffusion
- predicting the effect of enzyme inhibitors
- confusing alleles with genes
In the assignment, many candidates did not make a valid comparison between their data and the source data. Conclusions often restated results instead of answering the aim. Evaluations named problems but did not suggest improvements.
The report advised regular practice with questions set in unfamiliar contexts. It stressed the difference between describe and explain. For graphs, it advised linear scales starting from a common zero.
Using past papers
Older papers are longer than the new 80-mark paper. Use them as full timed practice, or set yourself a 2-hour limit on the first 80 marks. Mark with the marking instructions and note the exact terms that earn credit.
Revision checklist
Tick topics as you revise. Ticks are saved on this device only.
- Make a glossary of key terms such as allele, gene, phenotype and genotype.
- Practise osmosis questions that predict mass gain or loss in different solutions.
- Learn the stages of mitosis in order and the event that marks each one.
- Compare diffusion, osmosis and active transport in a single table.
- Explain how inhibitors affect enzyme activity using a graph.
- Learn how a respirometer and a potometer work and what each measures.
- Practise percentage, average and ratio calculations from tables of data.
- Draw line graphs with linear scales and a common zero, labelled with units.
- Write one assignment aim, then a conclusion that answers that aim directly.
- For each evaluation point, add how to improve the experiment.
Quick answers
- How long is the National 5 Biology exam in 2027?
2 hours. The paper is worth 80 marks: 20 in Section 1 and 60 in Section 2.
- How much is the National 5 Biology assignment worth?
20 marks, which is 20% of the course. It is no longer scaled.
- When is the National 5 Biology exam in 2027?
Wednesday 12 May 2027, 13:00 to 15:00.