FOOD CHAINS

• What determines the abundance and distribution of organisms in an ecosystem?

  Biotic and abiotic factors
• Why do animals and plants have adaptations?


  To allow them to compete for resources
• What is an ecosystem?

  • The living organisms in a particular area
  • Non-living components of the environment
  • Interaction between community and environment
• What is a community in ecological terms?

  • All organisms that live in a habitat
  • Includes both plants and animals
• What is a population?

  • All members of a single species
  • Live within a geographical area
• What is a species?

  • A type of organism
  • Basic unit of classification
  • Individuals of different species cannot interbreed successfully
• How are organisms organized within an ecosystem?

  • Into levels: Producers, Primary consumers, Secondary consumers, Tertiary consumers
• What are producers in an ecosystem?

  Plants and algae that photosynthesize
• What are primary consumers?


  Herbivores that eat producers
• What are secondary consumers?

  Carnivores that eat primary consumers
• What are tertiary consumers?

  Carnivores that eat secondary consumers
• What is interdependence in an ecosystem?

  • All organisms depend on each other
  • Changes in one population can affect others
• What happens to the rabbit population if foxes are killed in a food chain?

  The rabbit population would increase
• What is a food chain?

  A sequence of feeding relationships between organisms
• What is the consequence of small changes in ecosystems?

  They can have large and unpredictable consequences
• What is competition in ecosystems?


  • Organisms compete for resources
  • Can be interspecific (between different species) or intraspecific (within the same species)
• What do photosynthesizing plants and algae compete for?

  Light, space, water, and minerals from the soil
• What do animals in an ecosystem compete for?

  Food, mates, and territory
• What characterizes a stable community?

  • Population sizes remain relatively constant over time
  • Healthy balance with the environment
• What happens to the populations of grass, rabbits, and foxes in a stable community?

  They remain relatively constant
• What are the key components of an ecosystem?

  • Biotic factors (living organisms)
  • Abiotic factors (non-living components)
  • Interdependence among organisms