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?

1. Statement 1 correctly defines a food chain. It depicts a linear sequence of organisms where nutrients and energy are transferred as one organism is eaten by another. It illustrates the order of feeding relationships in an ecosystem. This statement is correct. 2. Statement 2 is incorrect. Food chains illustrate the feeding relationships *between* different species (different populations) at different trophic levels (e.g., producer, primary consumer, secondary consumer). They are not found *within* the population of a single species. 3. Statement 3 is incorrect. A food chain shows the pathway of energy flow (who eats whom), not the specific numbers of each organism involved. The quantitative representation of numbers, biomass, or energy at different trophic levels is depicted by ecological pyramids (pyramid of numbers, pyramid of biomass, pyramid of energy), not the food chain itself. 4. Therefore, only statement 1 is correct.