.1 levels of organisation

• photosynthetic organisms are the producers of biomass for life on Earth.
• Feeding relationships within a community can be represented by food chains. All food chains begin with a producer which synthesises molecules. This is usually a green plant or alga which makes glucose by photosynthesis.
• Producers are eaten by primary consumers, which in turn may be eaten by secondary consumers and then tertiary consumers.
• Consumers that kill and eat other animals are predators, and those eaten are prey. In a stable community the numbers of predators and prey rise and fall in cycles.