Biodiversity forms the basis for human existence in the following ways : 1. Soil formation 2. Prevention of soil erosion 3. Recycling of waste 4. Pollination of crops Select the correct answer using the codes given below :

Correct Option Biodiversity is fundamental to human existence by providing essential ecosystem services: - Soil formation: Microorganisms (bacteria, fungi) and invertebrates (earthworms, insects) decompose organic matter and mix soil, contributing to humus formation and soil structure, which is vital for agriculture. - Prevention of soil erosion: Plant roots bind soil particles, and vegetation cover reduces the impact of rain and wind, thereby preventing soil erosion and maintaining soil fertility. - Recycling of waste: Decomposer organisms, including bacteria, fungi, and detritivores, break down dead organic matter and waste products, returning nutrients to the ecosystem for reuse by producers. - Pollination of crops: A wide array of organisms like insects (bees, butterflies), birds, and bats facilitate the pollination of numerous crop species, which is crucial for food production and agricultural productivity. These services are categorized as supporting and regulating ecosystem services, directly underpinning human well-being. Incorrect Options Options (a), (b), and (c) are incorrect because they exclude one or more of the listed ecological services. All four points represent critical functions provided by diverse biological communities that are essential for human existence.

IAS 2011 — Environment & Ecology Environment & Ecology

2011mcqmedium

Biodiversity forms the basis for human existence in the following ways :

Soil formation
Prevention of soil erosion
Recycling of waste
Pollination of crops

Select the correct answer using the codes given below :

Official previous-year question

Verified 2 Aug 2026.

Options

A1, 2 and 3 only
B2, 3 and 4 only
C1 and 4 only
D1, 2, 3 and 4

Did you get this right?

Solution

Correct Option

Biodiversity is fundamental to human existence by providing essential ecosystem services:

Soil formation: Microorganisms (bacteria, fungi) and invertebrates (earthworms, insects) decompose organic matter and mix soil, contributing to humus formation and soil structure, which is vital for agriculture.
Prevention of soil erosion: Plant roots bind soil particles, and vegetation cover reduces the impact of rain and wind, thereby preventing soil erosion and maintaining soil fertility.
Recycling of waste: Decomposer organisms, including bacteria, fungi, and detritivores, break down dead organic matter and waste products, returning nutrients to the ecosystem for reuse by producers.
Pollination of crops: A wide array of organisms like insects (bees, butterflies), birds, and bats facilitate the pollination of numerous crop species, which is crucial for food production and agricultural productivity.

These services are categorized as supporting and regulating ecosystem services, directly underpinning human well-being.

Incorrect Options

Options (a), (b), and (c) are incorrect because they exclude one or more of the listed ecological services. All four points represent critical functions provided by diverse biological communities that are essential for human existence.

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