With reference to food chains in ecosystems, consider the following statements : 1. A food chain illustrates the order in which a chain of organisms feed upon each other. 2. Food chains are found within the populations of a species. 3. A food chain illustrates the numbers of each organism which are eaten by others. Which of the statements given above is/are correct?

Correct Answer: A) 1 only

Let's break down each statement:

Statement 1: A food chain illustrates the order in which a chain of organisms feed upon each other. This is correct. A food chain depicts the linear sequence of organisms through which nutrients and energy pass as one organism eats another. Statement 2: Food chains are found within the populations of a species. This is incorrect. Food chains involve different species interacting through feeding relationships. A population consists of individuals of a single species. Food chains describe interactions between species. Statement 3: A food chain illustrates the numbers of each organism which are eaten by others. This is incorrect. While a food chain shows who eats whom, it doesn't necessarily illustrate the quantities or numbers of organisms consumed. Food webs, or ecological pyramids, are better suited to represent numerical relationships. Therefore, only statement 1 is correct.