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Q59·GS Paper 1 · Prelims 2017

Biological Oxygen Demand measurement

EnvironmentEnvironmental quality assessmentFactual singleEasyStatic

Question

Biological Oxygen Demand (BOD) is a standard criterion for

(a) Measuring oxygen levels in blood (b) Computing oxygen levels in forest ecosystems (c) Pollution assay in aquatic ecosystems (d) Assessing oxygen levels in high altitude regions

Options

a

Measuring oxygen levels in blood

b

Computing oxygen levels in forest ecosystems

c

Pollution assay in aquatic ecosystems

Answer
d

Assessing oxygen levels in high altitude regions

Explanation

Biological Oxygen Demand (BOD) is a standard parameter for assessing water quality and pollution levels in aquatic ecosystems. BOD measures the amount of oxygen required by microorganisms to decompose organic matter in water—higher BOD indicates greater pollution and lower dissolved oxygen. Option (a) is incorrect; blood oxygen is measured differently (blood gas analysis). Option (b) is incorrect; forest ecosystem oxygen levels use different parameters. Option (d) is incorrect; altitude-related oxygen assessment uses different measures. BOD is specifically used as a water quality indicator in aquatic environments to measure organic pollution. > BOD = Aquatic Ecosystem Water Pollution Indicator (Microbial O₂ Consumption).

Answer: (c).

Question details

Year

2017

Paper

GS Paper 1

Question

Q59

Subject

Environment

Sub-topic

Environmental quality assessment

Type

Factual single

Difficulty

Easy

Nature

Static

Source hint

NCERT Environmental Studies

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