Edexcel, specification YBI11
Edexcel International A Level Biology
Edexcel International A Level Biology (YBI11) is sat as six unit exams: Units 1 to 3 for the International AS, then Units 4 to 6 for the full International A Level. Here are all 8 topics, with free revision notes, exam questions with mark schemes, flashcards and mind maps.
What do you want to do?
Revision notesShort notes for every spec point, with diagrams185 notesExam questionsExam-style questions with mark schemes305 questionsFlashcardsFlip, mark and practise what you don't know588 cardsMind mapsEach topic on one page8 mind mapsTopic testsPrintable tests with the mark scheme8 printable testsPracticalsMethod, variables and safety for each one22 practicalsVideos
Topics
All papers
Units 1, 2, 4 and 5 each test two topics; Units 3 and 6 test practical skills · Unit 1: 1 hour 30 minutes · Unit 2: 1 hour 30 minutes · Unit 3: 1 hour 20 minutes · Unit 4: 1 hour 45 minutes · Unit 5: 1 hour 45 minutes · Unit 6: 1 hour 20 minutes- 1Molecules, Transport and HealthWater, carbohydrates and lipids · The heart, blood vessels and haemoglobin · Cardiovascular disease and its causes · Health risks, evidence and treatment4 subtopics
- 2Membranes, Proteins, DNA and Gene ExpressionGas exchange, membranes and transport · Proteins and enzymes · DNA, the genetic code and gene expression · Inheritance, cystic fibrosis and genetic screening4 subtopics
- 3Cell Structure, Reproduction and DevelopmentCells, tissues and organelles · Microscopy and measuring cells · Chromosomes, meiosis and gametes · Mitosis and the cell cycle · Stem cells, gene expression and phenotype5 subtopics
- 4Plant Structure and Function, Biodiversity and ConservationPlant cells and cell walls · Plant tissues, fibres and mineral nutrition · Bacterial growth, plant medicines and drug testing · Classification and biodiversity · Niche, allele frequency and conservation5 subtopics
- 5Energy Flow, Ecosystems and the EnvironmentPhotosynthesis · Productivity and ecosystems · Climate change · Temperature, evolution and speciation4 subtopics
- 6Microbiology, Immunity and ForensicsCulturing and measuring microorganisms · Bacteria, viruses and infection · The immune response · Antibiotics and infection control · Decay, DNA techniques and forensics5 subtopics
- 7Respiration, Muscles and the Internal EnvironmentStages of respiration · Respiratory quotient and respiration practicals · Muscles and movement · The heart, ventilation and exercise · Homeostasis, hormones and the kidney5 subtopics
- 8Coordination, Response and Gene TechnologyNeurones, reflexes and the nervous system · Impulses, synapses and receptors · Plant responses · The brain and hormonal control · Gene technology5 subtopics
What the labels mean
- A Level only
- Only in the full A Level, not the AS Level. AS Level students can skip it.
Anything without a label is for everyone taking Edexcel International A Level Biology.
About Edexcel International A Level Biology
Pearson Edexcel International Advanced Level Biology (YBI11) is modular. The International AS (XBI11) is Units 1 to 3 and counts for half of the International A Level, which adds Units 4 to 6. Units 1, 2, 4 and 5 each examine two of the eight topics, and Units 3 and 6 are written papers on practical skills, based on the 18 core practicals. Topics 5 to 8 (Units 4 and 5) are labelled A Level only on this site. Every unit can be sat in January, June or October, and units can be resat. These notes follow the 2018 specification; Pearson has announced a new International A Level Biology for teaching from September 2027.
Unit 1: Molecules, Diet, Transport and Health
- Time
- 1 hour 30 minutes
- Marks
- 80 marks, 20% of the IAL (40% of the IAS)
- Topics
- Topic 1 Molecules, Transport and Health and Topic 2 Membranes, Proteins, DNA and Gene Expression
Unit 2: Cells, Development, Biodiversity and Conservation
- Time
- 1 hour 30 minutes
- Marks
- 80 marks, 20% of the IAL (40% of the IAS)
- Topics
- Topic 3 Cell Structure, Reproduction and Development and Topic 4 Plant Structure and Function, Biodiversity and Conservation
Unit 3: Practical Skills in Biology I
- Time
- 1 hour 20 minutes
- Marks
- 50 marks, 10% of the IAL (20% of the IAS)
- Topics
- A written paper on practical skills from Units 1 and 2 (core practicals 1 to 9): planning, measurements and processing results
Unit 4: Energy, Environment, Microbiology and Immunity
- Time
- 1 hour 45 minutes
- Marks
- 90 marks, 20% of the IAL
- Topics
- Topic 5 Energy Flow, Ecosystems and the Environment and Topic 6 Microbiology, Immunity and Forensics, with some synoptic questions on Units 1 and 2
Unit 5: Respiration, Internal Environment, Coordination and Gene Technology
- Time
- 1 hour 45 minutes
- Marks
- 90 marks, 20% of the IAL
- Topics
- Topic 7 Respiration, Muscles and the Internal Environment and Topic 8 Coordination, Response and Gene Technology. One 20-mark question is based on a scientific article released before the exam.
Unit 6: Practical Skills in Biology II
- Time
- 1 hour 20 minutes
- Marks
- 50 marks, 10% of the IAL
- Topics
- A written paper on practical skills from all units (core practicals 1 to 18), including planning an investigation to test a hypothesis
Edexcel International A Level Biology exams
- Level
- Untiered: everyone sits the same six units. The International A Level is graded A* to E, the International AS A to E
- Sittings
- January, June and October, unit by unit. Any unit can be resat
- January 2027
- Pearson publishes a timetable for each series. Your school enters you unit by unit, so check your dates and start times with your exams officer.
- Grade boundaries
- Pearson Edexcel grade boundaries (see the International Advanced Level files). They change every series.
Edexcel IAL Biology guide: units and exam series · Edexcel International A Level Biology past papers