Biology · Ecosystems · NEET
A food chain is a single straight path of eating, like grass to goat to man. A food web is many such chains joined together, because one organism is eaten by several predators and one predator eats several prey. So a food chain is one line, but a food web is a whole network of lines. For NEET, remember that food webs are more realistic than a single chain.
A food web forms because most animals do not eat only one food. NCERT gives the example that cockroaches, crows and humans are omnivores, so they belong to more than one food chain at the same time. When these many chains cross and connect, they make a food web. This is why real ecosystems almost never have just one simple chain.
Yes. Every organism in a food web still sits at a trophic level based on what it eats. Producers are the first trophic level, herbivores (primary consumers) are the second, and carnivores come after. In a web, one animal like a crow can appear at more than one trophic level because it eats different foods. NEET often tests this exact idea with grassland examples.
A food web matters because it gives the ecosystem stability. If one prey species is removed, a predator in a web can switch to another food, so it does not starve at once. In a single food chain, losing one link can break the whole chain. So food webs make energy flow more reliable and the community harder to collapse.
No, but they are linked. A food web shows the eating connections (who eats whom), while energy flow describes how the energy actually moves and decreases along those connections, following the 10 per cent law. The web is the map of paths, and energy flow is what travels through those paths. You study energy flow next, right after food webs.
Match the trophic levels (grassland ecosystem) in Column I with the correct species in Column II. Column I: (a) First trophic level (b) Second trophic level (c) Third trophic level (d) Fourth trophic level. Column II: (i) Crow (ii) Vulture (iii) Rabbit (iv) Grass. Select the correct option:
Which of the following are primary consumers in a food chain?
Try the real previous-year questions from this chapter — each with the answer and a full solution.
A food web is many food chains joined together in one ecosystem. It shows all the eating links between producers, consumers and decomposers, not just one straight line.
NCERT explains food webs in the Ecosystem chapter, saying that the natural interconnection of food chains, caused by omnivores like crows and cockroaches, makes a food web.
Because a predator in a web has many food options. If one prey is gone, it eats another, so the ecosystem does not collapse. A single food chain breaks if one link is lost.
Yes. Omnivores such as humans, crows and cockroaches eat both plants and animals, so they belong to several food chains at once, and this is what creates the web.
Yes. Energy still transfers along each link, and only about 10 per cent passes to the next level. The web only shows the paths; energy flow describes how much moves along them.
