A network different food chains operating in a given ecosystem is called food web. Actually single food chain does not operate in an ecosystem. Every food chain consists of producers and different consumers. In the given food web the two food chains are given below:
Tree → Insect → Frog → Snake → Hawk.
Plants → Deer → Wolf.
In the 1 food chain, tree is producer, insect is primary consumer, frog is the secondary consumer, snake is tertiary consumer and hawk is the top consumer. In the 2 food chain, Plants are producer, deer is primary consumer and wolf is the consumer.
This is usually called a placebo. They are used as control tests to make sure that a product actually works. A placebo, however, is not merely restricted to pills, though.
