Pearson Edexcel · A Level · 9BI0
Biology — Keywords & Key Terms — Definitions Glossary (2026)
Pearson Edexcel A Level Biology B (9BI0)
Topic-by-topic keywords, key terms and definitions for precise exam language—separate from our revision checklists (topic coverage) and formula sheets (equations).
Keywords & Key Terms — definitions
Examiner-style keywords and definitions organised by syllabus topic. Terms are tagged Essential (start here), Core (typical exam standard), and Advanced for harder distinctions — tick each row when you can recall it. Your progress is saved in this browser for this list.
Pearson Edexcel A Level Biology (9BI0)
Pearson Edexcel A Level Biology (9BI0)
Pearson Edexcel A Level Biology B (9BI0)
Pearson Edexcel Biology B (9BI0) topics 1–10 cover biological molecules, cells/viruses and reproduction, classification and biodiversity, exchange and transport, energy for biological processes, microbiology and pathogens, modern genetics, origins of genetic variation, control systems, and ecosystems — assessed across Papers 1–3.
Mark schemes: Pearson Edexcel rewards precise biological terminology — gene, allele, locus, homozygous, heterozygous — and clear linked reasoning in extended responses. Statistical conclusions must compare calculated and critical values with explicit reference to the null hypothesis. Quote figures with units when describing data trends and use comparative language when contrasting conditions.
Active recall: 0 / 20 terms ticked
| Recalled | Topic | Level | Keyword | Definition |
|---|---|---|---|---|
| Cells & exchange | Essential | Surface area to volume ratio | Falls as organisms get larger, driving the need for specialised exchange surfaces. | |
| Cells & exchange | Core | Fick's law | Rate of diffusion ∝ (surface area × concentration difference) ÷ diffusion distance. | |
| Cells & exchange | Core | Water potential | Tendency of water to move by osmosis: ψ = ψs + ψp; water moves from higher to lower ψ. | |
| Cells & exchange | Core | Active transport | Movement of substances against a gradient using ATP and specific carrier proteins. | |
| Cells & exchange | Advanced | Cooperative binding | Binding of one O₂ to haemoglobin increases affinity for further O₂ molecules. | |
| Energy for biological processes | Core | Photosynthesis — Calvin cycle | Light-independent fixation of CO₂ via RuBisCO into GP, TP and regeneration of RuBP. | |
| Energy for biological processes | Core | Glycolysis–link–Krebs–ETC | Sequence of respiration stages oxidising glucose to CO₂ and water with ATP yield. | |
| Energy for biological processes | Core | Gross primary productivity | Rate at which producers convert light energy to chemical energy in biomass. | |
| Energy for biological processes | Core | Net primary productivity | NPP = GPP − plant respiratory losses; energy available to next trophic level. | |
| Energy for biological processes | Advanced | Respiratory quotient | RQ = CO₂ produced ÷ O₂ consumed; indicates the substrate being respired. | |
| Genetics & evolution | Core | Semi-conservative replication | Each daughter DNA duplex contains one parental and one newly synthesised strand. | |
| Genetics & evolution | Core | Monohybrid inheritance | Single-gene cross giving a 3:1 phenotypic ratio in F2 from heterozygous parents. | |
| Genetics & evolution | Core | Dihybrid inheritance | Two-gene cross giving a 9:3:3:1 phenotypic ratio with independent assortment. | |
| Genetics & evolution | Core | Hardy–Weinberg principle | p² + 2pq + q² = 1 predicts allele frequencies in a non-evolving population. | |
| Genetics & evolution | Advanced | χ² goodness-of-fit | Tests whether observed counts deviate significantly from those expected by a genetic model. | |
| Coordination & ecology | Core | Homeostasis | Maintenance of a stable internal environment via negative feedback around a set point. | |
| Coordination & ecology | Core | Negative feedback | Mechanism that reverses a deviation from a set point to restore equilibrium. | |
| Coordination & ecology | Core | Simpson's index of diversity | D = 1 − Σ(n/N)²; higher D indicates greater biodiversity in a community. | |
| Coordination & ecology | Core | Spearman's rank rs | Non-parametric correlation coefficient between two ranked variables; range −1 to +1. | |
| Coordination & ecology | Advanced | Nutrient cycling | Movement of carbon and nitrogen through reservoirs via fixation, decomposition and respiration. |
Pair this with our revision checklists, formula sheets hub and past paper finder.
Biology (9BI0) — Keywords & Key Terms FAQ
- What is on this Pearson Edexcel A Level Biology keywords and key terms list?
- It is a topic-organised glossary of important biology terms with short, exam-style definitions aligned to Pearson Edexcel A Level Biology B (9BI0) (9BI0). It is designed for “define”, “state”, “outline” and “explain” questions where precise vocabulary earns marks.
- How should I use this Biology glossary alongside past papers?
- Tick terms when you can recall them without reading the answer, then check your wording against mark schemes. Pair vocabulary practice with past papers for A Level Biology (9BI0) so you apply terms in context.
- Is this the same as a revision checklist or a formula sheet?
- No. Revision checklists help you track which syllabus topics you have covered and your confidence—separate pages on Tutopiya. Formula sheets summarise equations and quantitative relationships. This page is only a definitions and key-terms glossary for Biology.
- Can I download this Biology keywords and key terms list for free?
- Yes. After a quick free sign-up you can download a UTF-8 CSV (opens in Excel or Google Sheets) or open a print-friendly page and save as PDF. Browsing the list on the page is free.
- Is this Biology list aligned to the 9BI0 specification?
- Topic groupings and wording follow Pearson Edexcel A Level Biology B (9BI0) for Pearson Edexcel A Level. Always confirm final learning objectives and any regional options in your official specification and recent examiner reports for your exam session.
- Why focus on definitions instead of full notes?
- Mark schemes reward correct technical terms and clear links between ideas. A compact glossary lets you drill the exact language examiners expect for Biology at A Level, separate from longer notes or topic trackers.