Biology - topic 19

• Ecology

  Study of inter-relationships between organisms and the environment
• Abiotic factors

  Non-living - temperature, pH levels, light intensity
• Biotic factors

  Living - competition, predators
• Ecosystem

  Community and non-living factors of environment - lake
• Population

  1 species occupying a habitat at the same time and can interbreed
• Carrying capacity

  Size of population an ecosystem can support
• Community

  Populations of different species
• Habitat

  Where organisms live, characterised by physical conditions
• Microhabitat

  Smaller units with their own microclimate - crevice on tree bark
• Ecological niche

  How an organism fits into the environment
• Competitive exclusion principle

  2 species cannot occupy the same niche