Question

Give reason.
Energy flow through an ecosystem is “one way”.

Answer 1

Hint: In an ecosystem, different types of organisms are present. Some of these organisms are able to produce food and some depend on others for food. This interconnecting relationship between organisms in a particular environment for the food is known as a food web.

Complete answer:
The ultimate source of energy for life on earth is the sun energy. Living organisms have evolved special ways to harness the energy of the sun and use it for their own well-being. In due course, they have evolved special relationships and interactions which allowed energy to be transferred. Once the energy has been captured, it gets passed around through the various organisms in a particular area.
In a food web or food pyramid, there are a number of levels. At the base level, there are producers. The producers are the organisms who produced their own food and serve as the foundation for all food webs. Green plants, grass, algae, and even some bacteria act as producers. They make their own energy by converting carbon dioxide with the help of sunlight.
Then at the next level of the food web, there are primary consumers, who utilise the plants as their food and obtain energy from them. Examples of primary consumers are some insects, birds, horse deer, etc. Secondary consumers belong to the next level. These animals are fed on primary consumers and get energy. Snakes, coyotes, wolves, lions, and spiders are a few known examples of secondary consumers. After that, the tertiary consumers follow as they are the top predators.
The producers transform solar energy into chemical energy in the form of organic compounds. Then the primary consumers get their nutrition and energy from the producers. Only 10% of energy is passed from one trophic level to the other. The energy that is obtained by the producers from the sun does not revert to the Sun and the energy passed to the herbivores does not return to the producers. The energy always moves to the next trophic level in a unidirectional way. Therefore, the flow of energy through an ecosystem is always ‘one way’.

Note: The Food web is a network of food chains in an ecosystem where all are interconnected to each other. Each organism is eaten by the other organism and then those organisms are eaten by several other organisms, these series of organisms where one is dependent for food on another is called the food web. The flow of energy is unidirectional i.e. the energy never can be transferred back.