Grade 4 | Science | Food chain, food web, Animals and Birds, Olympiad, CBSE, ICSE, SOF, ITO
A series or sequence of links showing how nutrients and energy pass from one organism to another is called food chain. All food chains start from producers i.e. plants.
Plants are called producers as they make food with the help of sunlight, water, carbon dioxide and nutrients from the soil.
Animals like deer, grain-eating birds, rats etc are called primary consumers as they primarily consume plants. Thus primary consumers are mostly herbivorous or omnivorous.
Flesh-eating animals like snakes, lions etc are called secondary consumers as they eat primary consumers.
There could be a third link of consumers in some food chains called Tertiary consumers. Tertiary consumers eat secondary consumers. e.g. Eagle eats snake
Scavengers like hyena, vultures, crows etc feed on dead animals and they break down organic matter into smaller pieces.
Decomposers like bacteria, fungi, mushrooms, termites etc feed on organic matter and break them further. Nutrients are returned to the soil to be again used by plants. A food chain ends with a decomposer.
A network of interconnected food chains is called food web.