Ecology and the environment
- Organism in the environment
- Ecological terms
- Population
- Community
- Habitat
- Ecosystem
- Quadrat practical
- Random placement
- Mean per quadrat
- Estimate population
- Biodiversity and distribution Biology only
- Variety of species
- Transect for distribution
- Species per quadrat
- Abiotic factors
- Temperature
- Light
- Water
- Biotic factors
- Competition
- Predation
- Predator-prey cycles
- Ecological terms
- Feeding relationships
- Trophic levels
- Producers (level 1)
- Primary, secondary, tertiary consumers
- Decomposers
- Food chains and webs
- Arrows: food to eater
- Webs link chains
- Pyramids
- Number
- Biomass
- Energy transfer
- Energy transfer
- About 10%
- Faeces
- Respiration heat
- Urine
- Limited chain length
- Little energy left
- Less biomass higher up
- Trophic levels
- Cycles
- Carbon cycle
- Photosynthesis removes CO₂
- Respiration adds CO₂
- Combustion adds CO₂
- Decomposers
- Bacteria and fungi
- Decomposition
- Release CO₂
- Nitrogen cycle Biology only
- Nitrates for proteins
- Nitrogen fixation Biology only
- N₂ to nitrogen compounds
- Root nodules
- Nitrification Biology only
- Ammonium to nitrates
- Denitrification Biology only
- Nitrates to N₂
- Carbon cycle
- Human influences
- Sulfur dioxide
- Acid rain
- Lakes and trees
- Lichens
- Carbon monoxide
- Incomplete combustion
- Binds haemoglobin
- Greenhouse gases
- CO₂, CH₄, N₂O
- CFCs
- Water vapour
- Enhanced greenhouse effect
- Infrared absorbed
- Global warming
- Sea level rise
- Sewage
- Oxygen used up
- Pathogens
- Eutrophication
- Leached nitrates
- Algal bloom
- Oxygen falls
- Deforestation Biology only
- Leaching
- Soil erosion
- Less evapotranspiration
- More CO₂
- Sulfur dioxide