High-Frequency Question Types (2018–2023):

1. Microbe-product identification — "Which microbe produces ___?" or "The holes in Swiss cheese are produced by ___."

   • Tested almost every year. Know all food + industrial microbe-product pairs exactly.

2. BOD and sewage treatment — "High BOD indicates ___" or "Which stage of sewage treatment reduces BOD?"

   • NEET 2020 and 2023 tested BOD directly. Always: high BOD = high pollution; secondary treatment reduces BOD.

3. Biofertilizer identification — "Which organism is used as a biofertilizer in paddy fields?" or "Mycorrhiza helps in uptake of ___."

   • NEET 2018 and 2021 tested this. Paddy = cyanobacteria; legumes = Rhizobium; phosphorus = mycorrhiza.

4. Streptokinase source and function — "Streptokinase is obtained from ___" (NEET 2019, 2022).

   • Always answer: Streptococcus; it is a clot-buster enzyme, not an antibiotic.

Distractor Alert List:

• Lactobacillus as Swiss cheese hole maker (wrong — Propionibacterium)
• Rhizobium in paddy (wrong — Anabaena/Nostoc)
• Mycorrhiza for nitrogen (wrong — phosphorus)
• Streptokinase as antibiotic (wrong — enzyme/thrombolytic)
• Penicillium notatum for cheese (wrong — Roquefort = Penicillium roqueforti)

Command Words in NEET MCQs:

• "Primarily helps" → look for the most critical/direct function (e.g., mycorrhiza "primarily" = phosphorus)
• "Is obtained from" → exact organism source required
• "Indicates" in BOD context → always pollution level

Preparation Tip: Build a 3-column flashcard table: Microbe | Product | NEET Trap. Drill it until you can reconstruct it from memory.