Key concepts in biology
- Cells
- Animal cell
- Nucleus
- Cell membrane
- Mitochondria
- Ribosomes
- Plant cell
- Cell wall
- Chloroplasts
- Vacuole
- Bacterial cell
- Chromosomal DNA
- Plasmid DNA
- Ribosomes and membrane
- Flagella
- Sperm cell
- Acrosome
- Haploid nucleus
- Mitochondria
- Tail
- Egg cell
- Nutrients
- Haploid nucleus
- Membrane changes
- Ciliated epithelial cell
- Cilia move mucus
- Animal cell
- Microscopy and units
- Light microscope
- Light and glass lenses
- Lower magnification
- Lower resolution
- Electron microscope
- Higher magnification
- Higher resolution
- More sub-cellular detail
- Estimation
- Check answers
- Exact value not needed
- Units
- milli 10⁻³
- micro 10⁻⁶
- nano 10⁻⁹
- pico 10⁻¹²
- Standard form Higher tier
- Number × power of ten
- Calculate with it
- Magnification
- Image ÷ real size
- Labelled drawings
- Light microscope
- Enzymes
- Biological catalysts
- Proteins
- Not used up
- Active site
- Complementary shape
- Specific
- Denaturing
- Active site changes shape
- Temperature
- Optimum
- Denatured when high
- Substrate concentration
- Rate then plateau
- pH
- Optimum pH
- Extreme pH denatures
- Core practical: pH
- Amylase and starch
- Iodine
- Rate calculations
- Product ÷ time
- Biological catalysts
- Enzymes in the body and food
- Breakdown
- Sugars
- Amino acids
- Fatty acids and glycerol
- Synthesis
- Carbohydrates
- Proteins
- Lipids
- Breakdown
- Transport in cells
- Diffusion
- High to low
- No energy
- Osmosis
- Water only
- Partially permeable membrane
- Active transport
- Against gradient
- Energy from respiration
- Factors for diffusion
- Gradient
- Temperature
- Surface area
- Core practical: potatoes
- Cylinders in solutions
- Mass change
- Percentage change
- (final − initial) ÷ initial × 100
- Diffusion