Biology · Edexcel International iGCSE Biology (Pearson)

3ESO Biology — Study and Revision Guide for the School Year

I. Introduction

This guide is calibrated against the official Oak House School 3º ESO 2026–2027 booklist (school email 'Books and Materials - ESO 3 - 2026-27', June 2026): textbook names, publishers and ISBNs match the booklist; unit order follows the usual arrangement of each textbook — the actual teaching order set by your teacher takes precedence.

Language of instruction (confirmed by parent, October 2026): Biology is taught in English (Edexcel International iGCSE textbook, fully in English); exams are answered in English, and the glossary uses English terms.

The textbook is the Edexcel International iGCSE (9-1) Biology Student Book (Pearson, ISBN 9780435185084) — the same book as in 2nd ESO, so returning students do not need to buy it again. This guide organises units around the five Edexcel syllabus sections.

How to use: read section II (year overview) first for the big picture, then work through section III (unit-by-unit outline), keeping the glossary (IV) at hand.

Exam Focus — End of Term Exams (26 Nov – 2 Dec)

Biology exam: Tuesday 1 December, 09:15–09:55 (40 minutes). It covers all the content studied so far in the IGCSE Biology course:

Topics in the exam

• Ecology (studied in 2nd ESO — new students will not answer these questions, but anyone choosing Biology in 4th ESO must study ecology as part of the GCSE course).
• The nature of organisms: organic molecules, stem cells, thermoregulation, cell respiration.
• Adaptation: evolution by natural selection.

How to revise

• The exact content required is in the 'basic knowledge questions' booklet (printed copy, also as a PDF on Google Classroom if you lose yours).
• Use the keywords in the basic knowledge questions plus the index at the back of the textbook to find the matching pages (a PDF of the textbook is also on Google Classroom).
• Practice exam questions are available via a link on Google Classroom, and a study guide is printed in the booklet.

II. Year Overview

This year's Biology follows the five Edexcel syllabus sections of the Edexcel International iGCSE (9-1) Biology Student Book (Pearson, ISBN 9780435185084): 1) the nature and variety of living organisms; 2) structures and functions in living organisms; 3) reproduction and inheritance; 4) ecology and the environment; 5) use of biological resources. It is the same book as in 2nd ESO — 3rd ESO goes deeper towards IGCSE level.

Why it matters for the future: the 4th ESO IGCSE Biology exam is essentially a harder version of these same five sections. If you can now draw the core processes (photosynthesis, blood circulation, genetic diagrams) from memory and know the English terms, 4th ESO will be a step up in difficulty, not a re-learn of concepts.

III. Unit-by-Unit Outline

Organised below by the five Edexcel syllabus sections (usual teaching order within each section — check the textbook contents for the exact subsections).

Section 1: The nature and variety of living organisms

What to learn: the common characteristics of life (MRS H GREN: movement, respiration, sensitivity, growth, reproduction, excretion, nutrition); eukaryotes vs prokaryotes; pathogens (bacteria, viruses, fungi) and infectious disease. What is tested: writing MRS H GREN from memory, matching pathogen types.

Section 2a: Cells, biological molecules and transport

What to learn: cell structures (cell membrane / cytoplasm / nucleus, chloroplast, mitochondria); levels of organisation; the structure of carbohydrates, proteins and lipids, and food tests; enzyme properties and factors affecting them; diffusion, osmosis, active transport. What is tested: identifying plant/animal cell diagrams, enzyme experiment design, osmosis U-tube problems.

Section 2b: Nutrition — photosynthesis in plants and digestion in humans

What to learn: the photosynthesis equation, leaf structure, limiting-factor experiments; the human digestive tract and glands; absorption by villi; balanced diet. What is tested: analysing variables in photosynthesis experiments, digestion flowcharts, conditions for enzyme action.

Section 2c: Respiration and gas exchange

What to learn: aerobic and anaerobic respiration equations; gas exchange in the alveoli; stomata and transpiration in plants. What is tested: writing respiration equations, comparing anaerobic products (humans vs yeast).

Section 2d: Transport and excretion

What to learn: heart structure and double circulation; blood components (red blood cells / white blood cells / platelets / plasma); xylem and phloem in plants; the kidney and urine formation (filtration — reabsorption). What is tested: blood circulation pathway diagrams, the urine formation process, blood pressure.

Section 2e: Coordination and response

What to learn: neurones and reflex arcs; central and peripheral nervous systems; hormones (insulin and blood-glucose negative feedback is a must-know); tropisms in plants. What is tested: the order of reflex arc stages, explaining negative feedback (the diabetes example), matching hormones to functions.

Section 3: Reproduction and inheritance

What to learn: sexual and asexual reproduction; the human reproductive system and the menstrual cycle; DNA, genes, chromosomes; single-gene inheritance diagrams (Punnett squares); natural selection and evolution. What is tested: genetic diagram calculations (dominant/recessive ratios), the four-step account of natural selection.

Section 4: Ecology and the environment

What to learn: food chains/webs and energy flow (the 10% rule); the carbon, nitrogen and water cycles; air pollution, the greenhouse effect, water pollution, deforestation. What is tested: energy pyramid calculations, carbon cycle diagram completion, essays on human impact on the environment.

Section 5: Use of biological resources

What to learn: crop growing (fertilisers, pests); microbes in food production (yeast, yoghurt); selective breeding; genetic engineering and GMOs. What is tested: describing the steps of genetic modification, comparing selective breeding vs genetic engineering.

IV. Key Glossary

V. Study Methods

• Draw it yourself: after each system, close the book and sketch the structure from memory, marking the direction of material flow. If you can draw it, you truly know it.
• Flow mnemonics: turn long processes into mnemonics — e.g. digestion 'mouth–oesophagus–stomach–intestines', circulation 'right heart to lungs, left heart to body'.
• Comparison tables: nervous vs hormonal control (speed, duration, mode of action) in a side-by-side table — comparison questions come up every year.
• Link to life: when studying blood-glucose control, think about why diabetics measure their blood sugar; when studying immunity, think about your own vaccination — abstract ideas become concrete at once.
• Experiment questions: biology exams often test experiment design (control groups, variable control) — collect the classic experiment from each unit separately.
• Structure–function–disease as one: after each system, attach common diseases to their structures — e.g. alveoli–pneumonia, islets–diabetes — exams love combined questions.
• Draw hormonal control as a loop: glucose rises — insulin secreted — glucose falls — secretion drops. A circle makes negative feedback obvious.

VI. Exam Skills

How to tackle diagram questions (half of a biology exam)

• Step 1, read the diagram: title, axes, legend — work out what it shows. Step 2, locate: match structures or curves to textbook knowledge. Step 3, terminology: answers must use formal terms, never everyday descriptions. Step 4, explain: the physiological mechanism behind what the diagram shows.

Process questions

• Write every stage in order — one stage, one mark; a skipped step loses a mark. Then check arrow directions: is the flow of matter or information one-way, or a cycle?

Essays (e.g. how vaccines work, healthy habits)

• Structure: define the concept — explain the mechanism — link to real life — conclude. For health topics, always name concrete behaviours (balanced diet, regular exercise, no smoking or alcohol); empty generalities score nothing.
• Matching questions are free marks: make structure–function cards per system and flip through them before the exam.
• Finding variables in experiments: the single difference between the two setups is the independent variable; phrase conclusions as 'when …, …' going from the independent to the dependent variable.

VII. Revision Rhythm for the Year

• September–October: levels of organisation and the digestive system; start drawing the first set of system diagrams.
• November–January: respiratory, circulatory and excretory systems; flow mnemonics mastered; introduction to nervous control.
• February–April: endocrine system and reproduction; focused work on hormone feedback; health and disease unit.
• May–June: draw all four system flowcharts from memory (full revision); timed diagram-question practice; quick pass over the geology section.