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Biology (XBI11)
5 sections available · 36 chapters available
Free Biology (XBI11) revision notes for Pearson Edexcel International AS Level students. Each chapter covers a key topic with worked examples and practice prompts you can take straight into the thinka app.
Topic 1: Molecules, Transport and Health (Unit 1)
Water, Carbohydrates and Lipids
Mass Transport and the Circulatory System
The Heart and the Cardiac Cycle
Haemoglobin and Gas Transport
Atherosclerosis, Blood Clotting and CVD Risk
Diet, Health Data and Interpreting Risk
Topic 2: Membranes, Proteins, DNA and Gene Expression (Unit 1)
Gas Exchange Surfaces and Fick's Law
Cell Membranes and Transport Across Them
Amino Acids, Proteins and Enzymes
DNA Structure and Replication
The Genetic Code, Protein Synthesis and Mutations
Monohybrid Inheritance and Sex Linkage
Cystic Fibrosis and Genetic Screening
Topic 3: Cell Structure, Reproduction and Development (Unit 2)
Eukaryotic and Prokaryotic Ultrastructure
Microscopy, Magnification and Resolution
Meiosis, Linkage and Genetic Variation
Gametes and Fertilisation
Mitosis, the Cell Cycle and Mitotic Index
Stem Cells and Cell Differentiation
Gene Expression, Epigenetics and Continuous Variation
Topic 4: Plant Structure and Function, Biodiversity and Conservation (Unit 2)
Plant Cells, Starch and Cellulose
Plant Fibres, Tensile Strength and Sustainability
Mineral Ions and Antimicrobial Plant Substances
Drug Testing and Clinical Trials
Classification, Species and the Three Domains
Biodiversity, Niche and Adaptation
Hardy-Weinberg, Natural Selection and Speciation
Conservation: Zoos and Seed Banks
Unit 3: Practical Skills in Biology I
Planning an Experiment and Identifying Variables
Apparatus, Technique and Health and Safety
Measurement, Uncertainty and Systematic Error
Processing Data: Units, Significant Figures and Tables
Graphs, Trends and Determining a Gradient
Statistics: Mean, Standard Deviation, Chi-squared and t-test
Evaluating Methods, Results and Conclusions
Core Practicals 1-9 in Context
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