Which of the following is a biotic component of an ecosystem?

Step 1: Analyze the question The question asks which option is a biotic component of an ecosystem. "Biotic" refers to the living parts of an ecosystem.

Step 2: Explain the concept An ecosystem has two kinds of components:

• Biotic (living): plants, animals, fungi, bacteria and other microorganisms.
• Abiotic (non-living): soil, water, rainfall, light, temperature, air, pH, and so on.

Memory hint: "Bio" means life, so biotic means living.

Step 3: Work through the options

• A. Soil: Non-living, a physical (edaphic) factor. It contains living organisms, but soil itself is abiotic.
• B. Rainfall: Non-living, a climatic factor. It is abiotic.
• C. Light: Non-living, a climatic factor and an energy source. It is abiotic.
• D. Fungi: Living organisms such as mushrooms, moulds and yeast. They act as decomposers in the ecosystem, so they are biotic.

Step 4: Answer The correct option is D. Fungi.

Exam tip: When you see "biotic" vs "abiotic," ask yourself, "Is it alive or was it once alive?" Rainfall, light, soil, temperature and wind are always abiotic. Plants, animals, fungi and bacteria are always biotic. Keep practicing, you are doing well!