food chains always start with a producer . producers produce their own food using energy from the sun
producers are usually green plants or algae- they make glucose by photosynthesis
when a green plant produces glucose, some of it is used to make other biological molecules in the plant- these are the plants biomass (mass of living material)
biomass can be thought of as energy stored in a plant
energy is transferred through living organisms in an ecosystem where organisms eat other organisms
producers are eaten by primary consumers, these are then eaten by secondary consumers. secondary consumers are eaten by tertiary consumers
consumers that hunt and kill other animals are called predators, they eat prey.
in a stable community containing prey and predators, the population of any species is limited by the amount of food available.
if population of prey increases, then so will population of predators. If number of predators increase, population of prey decrease
predator-prey cycles are always out of phase with each other because it takes a while for one population to respond to changes of the other population