Correct Option
The correct option is (c) 2 and 3 only.
Explanation
An ecosystem is a functional unit of nature where living organisms interact among themselves and also with the surrounding physical environment. It comprises two main components: biotic (living) and abiotic (non-living) factors. These components function together as a unified system through energy flow and nutrient cycling.
Statement-wise Analysis
- Statement 1 is Incorrect. An ecosystem is not limited to plants and animals; it also includes microorganisms (bacteria, fungi, etc.). These microorganisms act as decomposers and are essential for breaking down organic matter and recycling nutrients back into the soil.
- Statement 2 is Correct. Abiotic components, such as climate (temperature, rainfall, humidity), soil, water, and light, are integral parts of an ecosystem. They determine the type of organisms that can survive in a particular area and influence the overall functioning of the system.
- Statement 3 is Correct. Every organism in an ecosystem is part of a food chain or food web. Even small animals play critical roles (e.g., pollination, soil aeration, or serving as a food source for higher trophic levels). The removal or killing of small animals can disrupt these connections, leading to imbalances that significantly affect the ecosystem's stability.
Key Takeaway: An ecosystem is an integrated system composed of both biotic factors (plants, animals, and microorganisms) and abiotic factors (soil, climate). The elimination of any species, regardless of size, disrupts the food web and affects the ecosystem's equilibrium.