Ecology

• Decomposers


  Organisms which feed on dead and decaying organisms. They break down the biomass and release nutrients into the soil
• Consumers


  Feed on other organisms for their energy. Can be primary, secondary or tertiary
• Ecosystem


  The interaction between the living organisms and the different factors of the environment
• Biodiversity


  The variety of living organisms
• Carrion


  Decaying flesh and tissue of dead animals
• Competition


  The negative interaction between two or more organisms which require the same limited resource
• Producers

  Convert the sun’s energy into useful compounds through photosynthesis. They are green plants or algae
• Prey


  The animals which are eaten by the predators
• Community


  Made up of the populations of different species living in a habitat
• Interdependence


  The interaction between two or more organisms, where it is mutually beneficial
• Population


  The number of individual organisms of a single species living in a habitat
• Deforestation


  The removal and destruction of trees in forest and woodland
• Predators


  Organisms which kill for food
• Habitat


  Where a living organism lives
• Global warming

  The increase of the average global temperature
• The source of all energy in a food chain is the sun’s radiation. It is made useful by plants and algae which produce organic compounds through photosynthesis
• Scavengers


  Organisms which feed on dead animals (carrion)
• Abiotic factors

  • Moisture
  • Light
  • Temperature
  • CO₂
  • Wind
  • O₂
  • pH
• Species


  Organisms of similar morphology which can interbreed to produce fertile offspring
• Biotic factors

  • Predators
  • Competition
  • Pathogens
  • Availability of food
• When a living organism is consumed, some of the biomass and energy is transferred. Some of the energy is lost
• The arrow in a food chain indicates the direction of the flow of energy
• Populations of predators and prey increase and decrease in cycles. The size of the predator population depends on the size of the prey population and vice versa. Overall, there is a stable community
• Adaptations


  Specific features of an organism which enable them to survive in the conditions of their habitat
• A plant or animal will not physically change to adapt to its environment in its lifetime. Instead, there is natural variation within the species and only organisms whose features are more advantageous in the environment survive. The survivors then go on to reproduce and pass on their features to some of their offspring. The offspring who inherit these advantageous features are better equipped to survive. Charles Darwin described this process as ‘survival of the fittest’
• Types of adaptations

  • Structural adaptations
  • Behavioural adaptations
  • Functional adaptations
• Species will compete with one another and also within their own species to survive and to reproduce
• Parasitism occurs when a parasite only benefits from living on the host
• Mutualism occurs when both species benefit from a relationship
• Plants compete for resources including light, water, space and minerals
• Animals compete for resources such as food, water and space/shelter. They may also compete within their own species for mates
• Parasitism


  Occurs when a parasite only benefits from living on the host
• Deforestation and Land Use
• Animals compete for resources

  Food, water, space/shelter
• Plants do not need to compete for food
• Mutualism


  Occurs when both species benefit from a relationship
• Plants compete for resources

  Light, water, space, minerals
• All resources are needed for photosynthesis so the plant can make its own food
• Burning peat releases a lot of carbon dioxide into the atmosphere contributing to the greenhouse effect
• Peat bogs are produced when decomposition occurs over a very long time