大象传媒

Adaptations, interdependence and competition - EdexcelCommunities and populations

Organisms depend on each other for survival. This is called interdependence. Both living and non-living factors will affect the abundance and distribution of organisms in a habitat.

Part of Biology (Single Science)Ecosystems and material cycles

Communities and populations

There are a number of key terms within communities and populations:

  • an is the interaction between a of living organisms and their environment
  • the consists of all the conditions that surround any living organism - both the other living things and the non-living things or physical surroundings
  • a is all the organisms of the same or closely-related in an area
  • an ecosystem is two or more populations of organisms (usually many more) in their environment
  • a is the place where an organism lives
  • a is two or more populations of organisms
Oak tree environment. Root and litter zone has bacteria, earthworms, wood lice and funghi. Trunk has insects and larvae. Branches and leaves have bees, wasps, moths, squirrels, bluetits and hawks.
Figure caption,
A woodland ecosystem showing the habitats of different species.

Levels of organisation within an ecosystem

Organisms within an ecosystem are organised into levels.

ProducerProducers are plants and algae, which photosynthesise.
Primary consumerPrimary consumers are herbivores, which eat producers.
Secondary consumerSecondary consumers are carnivores, which eat primary consumers.
Tertiary consumerTertiary consumers are also carnivores. They eat secondary consumers.
Producer
Producers are plants and algae, which photosynthesise.
Primary consumer
Primary consumers are herbivores, which eat producers.
Secondary consumer
Secondary consumers are carnivores, which eat primary consumers.
Tertiary consumer
Tertiary consumers are also carnivores. They eat secondary consumers.