Primary vs Secondary Sewage Treatment — NEET Biology
📚 Practice ConceptWhat is the key difference between primary and secondary sewage treatment?
Assertion (A): Secondary sewage treatment involves mechanical agitation to promote microbial activity. Reason (R): Primary effluent is passed into large settling tanks where it is constantly agitated mechanically.
View solution & NCERT explanation
Correct answer: C — If assertion is true but reason is false.
NCERT confirms secondary treatment uses mechanical agitation (Assertion true). However, NCERT states “Primary effluent is passed into large aeration tanks where it is constantly agitated mechanically” - the Reason incorrectly places this in settling tanks instead of aeration tanks, making it false. This tests understanding of where mechanical agitation occurs in the treatment process.
What does NCERT say about What key difference between?
Has this concept appeared in NEET?
Which chapter is this from?
Through deep analysis of NEET and NTA, 176 of the 180 ReNEET 2026 (June 21) questions were already in the MedicNEET question bank before the exam.
176/180MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.