TRANSFER OF ENERGY
All living organisms require energy in order to survive. Plants get their energy from Sunlight and Animals get theirs by eating plants or other animals. This method of obtaining and sustaining energy takes place either in the form of a Food Chain or a Food Web.
Energy is transferred from one level to the next in the form of a Food Chain. Plants (Producers) are the chief source from which the transfer originates. Animals that feed on the plants are in turn fed upon by animals, which in turn get fed on by animal higher in the Hierarchy. As a result the transfer of energy takes place from plants to animals. This transfer of energy is called the Food Chain
EXAMPLES OF A FOOD CHAIN
When a large number of Food Chains exist in a Community, then they tend to form a Food Web. This is an inter-connection of food chains operating in an Ecosystem forming a Network where one organism in dependent on another for its survival. There is a linkage between various species of producers and consumers, suggesting that the food chains do not operate alone but instead rely on a Network of food chains called a Food Web.
A Food Chain represents the level at which organisms live off one another…It shows the transfer of Energy from one step or level to the next.
These steps or levels through which energy transfer takes place are called Trophic Levels, and can take place from the Primary Level to the Tertiary Level or from Producers to Consumers.
TRANSFER OF ENERGY IN FOOD CHAINS
Energy is not created in the Ecosystem. It is only converted from one form to another. Sunlight is the main source or provider of Energy. Without it Plants (Producers) cannot manufacture their food (Photosynthesis). The food produced by plants is stored as Chemical Energy and when consumed by Herbivores (Consumers) is transferred and utilized by the Herbivores, which in turn are eaten by Carnivores and Top Carnivores. (Top Consumers)
This form of Energy transfer and utilization takes place in the Food Chain at all Trophic Levels and is said to be Unidirectional. However, not all the energy is utilized and is lost to the Environment as Heat. This cannot be utilized by the Plants and as a result this flow of energy is said to be Unidirectional.