food chains

• food chains show what is eaten by what in an ecosystem
• a food chain starts with producers, which are plants that make their own food from sunlight using photosynthesis.
• when a green plant produces glucose, some of it is used to make other biological molecules in the plant
• the biological molecules inside green plants are called its biomass
• producers are eaten by primary consumers
• primary consumers are eaten by secondary consumers
• secondary consumers are eaten by tertiary consumers
• consumers that hunt and kill other animals are called predators
• in a stable community containing prey and predators, the population of any species is usually limited by the amount of food available
• if the population of prey increases in a stable community, then so will the population of the predators
• predator-prey cycles are always out of phase with each other