Biotic and Abiotic Factors

Biotic and abiotic factors are two types of components that affect an ecosystem. Biotic factors are living organisms or their products that directly or indirectly influence an ecosystem. On the other hand, abiotic factors are non-living components such as temperature, water, sunlight, soil, air, etc., that also have an impact on an ecosystem.

Explanation of Options

a) Light: Light is an abiotic factor. It is a form of energy that is essential for photosynthesis, which is the process by which plants convert sunlight into food. While light is necessary for the growth and survival of living organisms, it is not a living organism itself.

b) Air: Air is also an abiotic factor. It is composed of various gases such as oxygen, nitrogen, carbon dioxide, etc. Although air is vital for respiration, it is not a living organism or a product of a living organism.

c) Soil: Soil is an abiotic factor. It is a mixture of minerals, organic matter, water, and air. While soil provides nutrients and a medium for plant growth, it is not a living organism.

d) Saprophyte: The correct answer is option 'D'. A saprophyte is a type of organism that feeds on dead and decaying organic matter. It is a biotic factor because it is a living organism that directly influences the ecosystem by decomposing organic material and recycling nutrients back into the environment.

Conclusion

Among the given options, only the saprophyte is a biotic factor. Biotic factors are living organisms or their products that have a direct or indirect impact on an ecosystem. In this case, the saprophyte plays a crucial role in the decomposition and nutrient cycling processes within the ecosystem.