Question

Read the following statements (1 - 3) related to food web and select the correct statements ?

1. Food webs are formed because of complex feeding relationships between organisms.
2. Food web represents reality more closely than the food chain in an ecosystem.
3. Organisms generally feed at one trophic level in a food web.

• A. 1 and 3
• B. 2 and 3
• C. 1 and 2
• D. 1, 2 and 3

Answer 1

The correct option is C 1 and 2

A food chain refers to the sequence of organisms where one living organism eats another and a network of interconnected food chains in a community of different organisms forms a food web.

In a food web, one organism can consume multiple organisms and can itself be consumed by multiple organisms. Many living organisms are omnivores, they can be a part of grazing (begins with producers like plants) or detritus food chain (begins with dead or decaying organic matter). So, it is a complex feeding relationship between organisms. Hence statement 1 is correct.

Food web represents reality more closely than the food chain due to the following reasons.

• It helps in understanding ecological interactions that define energy flows and predator-prey relationships.
• It illustartes all possible transfers of energy and nutrients among the organisms in an ecosystem, whereas a food chain traces only one pathway of the food.
• If any of the intermediate organisms from a food chain is removed, it will disrupt the flow of energy and the organisms that depend on it will also die. It leads to instability of the ecosystem. Hence statement 2 is correct.

The food web provides more than one alternative for food to most of the organisms in an ecosystem and therefore increases their chance of survival. Therefore, one organism can occupy more than one trophic level in the food web. For example, when a bear eats berries, the bear is functioning as a primary consumer but when the same bear eats a plant-eating rodent, the bear is functioning as a secondary consumer. Hence statement 3 is correct.