GuidesBiologyPaper 1 · last-minute revision
3 days to go

GCSE Biology OCR B Paper 1: last-minute revision

Three days left. Every OCR B question opens with a real-world scenario before it asks any biology, so recall alone won't get you there. Paper 1 covers genes, keeping healthy, and life on Earth. Here's where to spend your time.

OCR Twenty First Century Science B, J257
The plan

Your 3-day plan

One focus per day, building to a timed run. Work it in order.

3
3 days to go

You and your genes (B1)

  • Revise DNA and the genome: the double helix, base pairing, and how genes code for proteins. Practise applying this to an unfamiliar organism or scenario, since OCR B always frames questions with context rather than asking bare recall.
  • Practise Punnett square questions until predicting genotype and phenotype ratios is automatic, plus how sex is determined by X and Y chromosomes.
  • Revise genetic engineering and be ready for an evaluate-style question asking whether gene technology should be used. OCR B examines these 'should we...?' questions directly, so practise giving a scientific reason on both sides, not just an opinion.
2
2 days to go

Keeping healthy (B2)

  • Go through communicable and non-communicable disease, pathogen types, and how the body defends itself: skin, phagocytosis, and the specific immune response with antibodies and memory cells.
  • Revise vaccination and herd immunity, plus how lifestyle, environment and genetic factors together affect disease risk. OCR B likes questions that ask you to weigh up all three factors in one answer, not just describe one.
  • Learn how drugs are developed and trialled: the role of placebo controls and why double-blind trials are used. This is tested more explicitly on OCR B than most other boards.
1
1 day to go

Life on Earth: photosynthesis, plant nutrition and ecosystems, plus a full past paper

  • Revise the photosynthesis word and symbol equations, the role of chlorophyll, and the factors that limit the rate of photosynthesis: light, temperature and carbon dioxide.
  • Go through plant nutrition (xylem, phloem, root hair cells) and ecosystem interdependence: food webs, pyramids of biomass, decomposers and the carbon and nitrogen cycles.
  • Sit one full past paper under timed conditions and mark it against the scheme. Practise the true/false table and order-the-statements question formats, since OCR B uses these often and they catch students out under time pressure.
Priority order

The topics that come up most

Ranked from analysed past papers. Start at the top: if you run out of time, you will have covered the most-tested ground.

1

DNA, genes and genetic inheritance

DNA structure and inheritance questions appear throughout B1 in a real-world scenario, so you must be able to apply the biology to an unfamiliar context, not just recall definitions.

2

Genetic inheritance and Punnett squares

Genetic diagrams are a guaranteed calculation-style question. Practise them until working out ratios is second nature.

3

Pathogens, disease and the immune response

Communicable disease, pathogen spread and the body's defences form the core of B2 Keeping Healthy and appear across multiple questions on this paper.

4

Vaccination and herd immunity

How vaccines work and why herd immunity protects a population is consistently tested, often as an evaluate-style question about vaccination programmes.

5

Photosynthesis and limiting factors

The word equation, chlorophyll's role, and interpreting a limiting-factors graph are dependable sources of marks across the Life on Earth content.

6

Ecosystems, food webs and the carbon cycle

Constructing food webs, interpreting pyramids of biomass, and redrawing the carbon cycle from memory come up consistently in B3 content.

7

Genetic engineering and its ethics

OCR B examines 'should we use this technology?' questions directly. Learn the process and be ready to give a scientific reason for and against, not just an opinion.

8

Antibiotic resistance and evolution by natural selection

Antibiotic resistance is used as a modern example of evolution and links B1 genetics directly to disease treatment content in B2.

Your Knowledge Organisers

PrepWise has a one-page Knowledge Organiser for every topic above. In your final 3 days, use them the same way each time: cover the page, try to recall everything from memory, uncover and check what you missed, then repeat that topic again tomorrow.

Open the Biology Knowledge Organisers
Cheat sheet

Exam technique

Rules specific to Paper 1. On this paper, structure earns as many marks as knowledge.

1

Every question starts with a scenario: find the biology inside it

OCR B never asks bare recall questions. Read the context carefully first, identify which topic it's really testing, then apply what you know. Students who only memorise facts struggle here; students who understand the underlying biology can transfer it to any scenario.

2

True/false tables need careful, row-by-row reading

These appear often and catch students out when statements look similar. Read each row as its own complete claim rather than skimming the whole table at once, and don't assume the pattern of true/false answers looks 'balanced'.

3

'Should we...?' evaluation questions need scientific justification, not opinion

OCR B examines socio-scientific issues like genetic engineering, stem cells and biodiversity directly. Give a specific scientific reason for and against, then reach a justified conclusion. A one-sided opinion or a vague 'it depends' answer loses marks.

4

Order-the-statements questions test the whole process, not just the ending

When asked to sequence 4-5 lettered statements into the correct order, work through the underlying process step by step rather than guessing from memory. Getting the causal chain right matters more than recognising individual facts.

Avoid these

5 mistakes that cost marks

The errors examiners see most on this paper. Each one is an easy mark you already know how to keep.

Writing 'survival of the fittest' as the whole answer on natural selectionThat phrase alone earns no marks. You need the full chain: variation exists, some variants have an advantage, those individuals are more likely to survive and reproduce, so the allele becomes more common over generations.

Giving an opinion instead of a scientific justification on 'should we...?' questionsOCR B wants your answer grounded in biology: name a specific risk or benefit and explain the mechanism behind it, not just state whether you agree or disagree.

Confusing communicable and non-communicable diseaseCommunicable diseases are caused by pathogens and can spread between organisms. Non-communicable diseases are not caused by pathogens and cannot be passed on, even though lifestyle and genetic factors affect risk. Keep the definitions separate.

Saying antibiotics work on virusesAntibiotics only work on bacteria because they target processes bacterial cells have that human and viral cells don't. Viruses reproduce inside host cells, so antibiotics have nothing to target.

Reversing answers in a true/false table under time pressureSlow down on true/false tables specifically. It's easy to tick the wrong column when working quickly, and OCR B examiner reports flag this as a common, avoidable error.

Exam day

The morning of the exam

The 60 minutes before you walk in. Review what you know and settle your nerves.

  • Skim your Knowledge Organisers for genetic inheritance and vaccination one last time.
  • Re-read the photosynthesis word equation and say it out loud once.
  • Check you have a black pen, a spare pen, and a ruler for drawing genetic diagrams.
  • Do not attempt new topics this morning. Only review what you already know.
  • Remind yourself: every question has a scenario first. Find the biology being tested before you answer.
  • Eat something before you go in. A blood glucose crash mid-exam is avoidable.

Now test yourself

Reading this plan is not the same as being able to do it. Answer exam-style Biology questions in PrepWise, get them marked in seconds, and find the gaps while you still have time to fix them.

Practise Biology questions

Start the 3-day plan now

Open the Biology Knowledge Organisers, quiz every priority topic and walk in ready. Free during alpha.

Get started with your personalised revision
Get started with your personalised revisionStart here