B4 Ecosystems

B4.1 Ecosystems

• Ecosystems is made up of all the living organisms and physical conditions in an area.
• Organisms within the ecosystem are called the community.
• Area which the community lives in is called the habitat.
• Total number of organisms in each species is called a population.
• Organisms in a community can be divided into three groups:
• (Producers, Consumers, Decomposer)
• Producers - Organisms that make their own food by photosynthesis. (Plants and algae)
• Consumers - Organisms that cannot make their own food so as a result eat other organisms to gain energy. All animals are consumers.
• Decomposer - Special group of consumers. They gain energy by feeding on dead and decaying material.
• Food chain shows what an organism eats.
• Arrows in the food chain shows the transfer of biomass.
• Each step in the food chain is a trophic level.
• Food chains only show organisms eating one food source.
• In most communities, animals eat more than one type of organism.