24-03-2012, 12:00 PM
Food chain
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The feeding of one organism upon another in a sequence of food transfers is known as a food chain.
The chain of transfer of energy from one organism to another.
FOOD WEB
An interconnection of many food chains.
Topics to be discussed
Photosynthesis
Producers
Consumers
PRODUCERS
Organisms, such as plants, that produce their own food are called “Autotrophs”.
The Autotrophs, convert inorganic compounds into organic compounds.
They are called “Producers” because all of the species of the ecosystem depend on them.
Consumers
All the organisms that can not make their own food and need producers are called “Heterotrophs”.
In an ecosystem Heterotrophs are called “Consumers” because they depend on others.
They obtain food by eating other organisms.
TROPHIC LEVELS
The last word that is worth mentioning in this section is “Trophic level”, which corresponds to the different levels or steps in the food chain.
In other words, the producers, the consumers, and the decomposers are the main Trophic levels.
Ecological Pyramid
An ecological pyramid shows the relationship between consumers and producers at different trophic levels in an ecosystem
Shows the relative amounts of energy or matter contained at each trophic level
The Pyramid shows which level has the most energy and the highest number of organisms