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Common to Papers 1 and 2

Topic 1 - Key concepts in biology

1.1 - Cell structures and functionsCompare animal, plant and bacterial cells, and explain how each required sub-cellular structure helps the cell function. Use structure and function together to interpret unfamiliar cells.

1.2 - Specialised cellsExplain how sperm and egg cells are adapted for fertilisation and how ciliated epithelial cells clear the airways. Connect each feature to the biological job it makes possible.

1.3 - 1.5 - Microscopy, scale and unitsExplain how microscope technology reveals finer cell detail, estimate cell sizes and convert between milli-, micro-, nano- and picometres. A clearly marked Higher-tier part develops calculations in standard form.

1.6 - Microscopy practicalPrepare plant and animal specimens, bring them into focus and make labelled scientific drawings from observations. Use lens values, image sizes and scale bars to calculate magnification and actual size; all of this lesson applies to both tiers.

1.7 - 1.9 - Enzyme action and conditionsExplain how an enzyme’s active site makes its action specific, then use that mechanism to interpret changes in activity with temperature, pH and substrate concentration.

1.10 - 1.11 - Investigating enzyme activityInvestigate how pH affects the breakdown of starch by amylase. Plan valid measurements, understand the iodine endpoint and calculate enzyme activity from reaction times or product measurements.

1.12 - Building and breaking moleculesFollow enzyme-catalysed reactions that build carbohydrates, proteins and lipids or break them into smaller molecules. Explain why these reactions are essential for digestion, growth and repair.

1.13B - Food testsUse chemical reagents to identify starch, reducing sugars, proteins and lipids. Connect each method to its observation and use controls, separate samples and appropriate precautions to make conclusions trustworthy.

1.14B - Food calorimetryMeasure energy transferred from burning food to water, calculate an estimate per gram of food burned and explain why simple calorimetry usually underestimates food energy.

1.15 - Cell transportCompare diffusion, osmosis and active transport by what moves, the direction of net movement and the need for energy. Apply these mechanisms to cells and to changes in potato tissue.

1.16 - 1.17 - Osmosis practicalInvestigate how sucrose concentration changes potato mass. Use a controlled method, calculate percentage gains and losses and interpret the concentration at which there is no net water movement.

Paper 1

Topic 2 - Cells and control

2.1 - 2.4 - Mitosis and cell divisionFollow the cell cycle from chromosome copying to two genetically identical daughter cells. Explain why controlled mitosis supports growth, repair and asexual reproduction, and how loss of that control can lead to cancer.

2.5 - 2.7 - Growth and differentiationExplain how division, elongation and differentiation build growing organisms. Then use percentile charts to distinguish absolute growth from a child’s changing position in a reference group.

2.8 - 2.9 - Stem cellsCompare the functions of embryonic stem cells, animal tissue stem cells and plant meristems. Follow how cell replacement could restore tissue function and weigh evidence for medical benefits, risks and ethical concerns.

2.10B - Brain structure and functionLocate the cerebral hemispheres, cerebellum and medulla oblongata, and relate each to its functions. Explain how different regions can contribute to the same activity. This Biology-only lesson applies to both tiers.

2.11B - 2.12B - Brain imaging and treatmentUse CT and PET evidence to investigate brain function without opening the skull. Explain why spinal injuries and brain tumours can remain difficult to treat. This Biology-only lesson is Higher tier.

2.13 - 2.14 - Nerves, synapses and reflex arcsTrace how receptors detect a stimulus, neurones carry electrical impulses and synapses transfer the signal chemically. Use these structures to explain how a reflex moves a muscle rapidly without waiting for a conscious decision.

2.15B - How the eye worksFollow light through the eye, explain how rods and cones produce sensory information, and distinguish the iris response to light from lens accommodation. This Biology-only lesson applies to both tiers.

2.16B - 2.17B - Vision defects and correctionDistinguish focusing errors, cataracts and colour vision deficiency by where the fault occurs. Explain how lenses, corneal reshaping and lens replacement correct the appropriate defects. This Biology-only lesson applies to both tiers.

Topic 3 - Genetics

3.1B - 3.3 - Reproduction and meiosisCompare how sexual and asexual reproduction balance speed with genetic variation. Learn how meiosis produces genetically different haploid cells and why halving the chromosome number matters for sexual reproduction.

3.4 - 3.5 - DNA, genes and genomesBuild a DNA molecule from nucleotides and complementary base pairs, then distinguish a protein-coding gene from an organism’s whole genome.

3.6 - Extracting DNA from fruitFollow a fruit DNA extraction from broken tissue to a visible precipitate. Explain what each step does, what to keep after filtering, and why the collected material is a crude DNA-containing extract.

3.7B - 3.8B - Protein synthesisHigher tier: follow genetic information from DNA through transcription and translation to a folded protein. Connect the jobs of RNA polymerase, mRNA, ribosomes and tRNA to the order of amino acids.

3.9B - 3.10B - Genetic variants and proteinsHigher tier: compare two routes from a DNA variant to a changed characteristic. Use your knowledge of transcription and translation to distinguish changes in protein quantity from changes in protein shape and activity.

Topic 4 - Natural selection and genetic modification

Topic 5 - Health, disease and the development of medicines

Paper 2

Topic 6 - Plant structures and their functions

Topic 7 - Animal coordination, control and homeostasis

Topic 8 - Exchange and transport in animals

Topic 9 - Ecosystems and material cycles