Water Pollution and its Control — Prelims Strategy

Prelims Strategy

To excel in NEET questions on Water Pollution and its Control, aspirants should adopt a multi-faceted strategy. Firstly, master the definitions of key terms like BOD, COD, eutrophication, algal bloom, biomagnification, and activated sludge.

Understand the underlying processes thoroughly. For numerical problems (though rare, conceptual understanding of BOD is key), remember that high BOD implies high pollution and low dissolved oxygen. Secondly, memorize the sequence and specific processes involved in each stage of sewage treatment (primary, secondary, tertiary), focusing on the physical, biological, and chemical aspects respectively.

Pay close attention to the role of microbes (aerobic flocs, anaerobic digesters). Thirdly, be clear about the sources of different pollutants (domestic, industrial, agricultural) and their specific impacts (e.

g., heavy metals cause biomagnification, nutrients cause eutrophication). Practice identifying common water-borne diseases. When answering MCQs, carefully read the question and all options. For process-based questions, visualize the steps.

For 'NOT' type questions, eliminate the correct statements first. Be wary of trap options that might present a partial truth or a reversed relationship (e.g., high BOD means high oxygen).