The whole topic on one page. Each branch is one subtopic; read it out loud and try to explain every word.
Key concepts in biology
Cells
- Animal cellNucleusCell membraneMitochondriaRibosomes
- Plant cellCell wallChloroplastsVacuole
- Bacterial cellChromosomal DNAPlasmid DNARibosomes and membraneFlagella
- Sperm cellAcrosomeHaploid nucleusMitochondriaTail
- Egg cellNutrientsHaploid nucleusMembrane changes
- Ciliated epithelial cellCilia move mucus
Microscopy and units
- Light microscopeLight and glass lensesLower magnificationLower resolution
- Electron microscopeHigher magnificationHigher resolutionMore sub-cellular detail
- EstimationCheck answersExact value not needed
- Unitsmilli 10⁻³micro 10⁻⁶nano 10⁻⁹pico 10⁻¹²
- Standard formHigher tierNumber × power of tenCalculate with it
- MagnificationImage ÷ real sizeLabelled drawings
Enzymes
- Biological catalystsProteinsNot used up
- Active siteComplementary shapeSpecific
- DenaturingActive site changes shape
- TemperatureOptimumDenatured when high
- Substrate concentrationRate then plateau
- pHOptimum pHExtreme pH denatures
- Core practical: pHAmylase and starchIodine
- Rate calculationsProduct ÷ time
Enzymes in the body and food
- BreakdownSugarsAmino acidsFatty acids and glycerol
- SynthesisCarbohydratesProteinsLipids
- Food testsTriple onlyIodine: starchBenedict's: sugarsBiuret: proteinEthanol: fats
- CalorimetryTriple onlyBurn foodHeat waterEnergy per gram
Transport in cells
- DiffusionHigh to lowNo energy
- OsmosisWater onlyPartially permeable membrane
- Active transportAgainst gradientEnergy from respiration
- Factors for diffusionGradientTemperatureSurface area
- Core practical: potatoesCylinders in solutionsMass change
- Percentage change(final − initial) ÷ initial × 100