NEET Previous Year Question Patterns — Biological Classification
Most Frequently Tested Topics (2016–2025)
| Topic | Approx. Frequency | Typical Question Format |
|---|---|---|
| Virus nucleic acid (DNA or RNA, never both) | Every 1–2 years | "Viruses contain..." / "Which is NOT a characteristic of viruses?" |
| Fungi cell wall (chitin) and energy storage (glycogen) | Every 2–3 years | "Cell wall of fungi is made of..." / "Fungi store energy as..." |
| Diatomaceous earth / diatom frustules | Every 2–3 years | "Diatomaceous earth is formed by..." / "Cell wall of diatoms is..." |
| Lichen — phycobiont/mycobiont and | Every 2–3 years | "Which component of lichen performs photosynthesis?" / "Lichens are indicators of..." |
| Fungi class identification (spore types) | Every 2–3 years | "Match the following" — class to spore/example |
| Viroid discoverer and characteristics | Every 3–4 years | "Viroids were discovered by..." / "Viroids differ from viruses in..." |
| Mycoplasma — cell wall absent, kingdom | Every 3–4 years | "Which organism lacks a cell wall?" |
| Cyanobacteria — heterocysts, kingdom | Every 2–3 years | "Heterocysts are associated with..." / "Cyanobacteria belong to..." |
| Protozoan locomotion (match the following) | Every 2–3 years | "Match Amoeba, Paramoecium, Plasmodium, Trypanosoma to locomotion type" |
| Prion — composition and disease | Every 3–5 years | "Mad cow disease is caused by..." / "Prions differ from viruses in..." |
Recurring Question Patterns to Master
- "Which of the following does NOT have a cell wall?" — Answer patterns: Mycoplasma (bacteria), Euglena (pellicle), Amoeba, animal cells. The answer is organism-specific.
- "Match the following fungi class to spore type" — Always confusing Ascomycetes with Basidiomycetes .
- "Which organism is mixotrophic?" — Euglena (Protista); not Mycoplasma, not yeast.
- "Identify the infectious agent with no nucleic acid" — Prion (always).
- Assertion-Reason format on viroids: "Viroids are smaller than viruses (Assertion) because they lack protein coats (Reason)" — both A and R are true, and R correctly explains A.
High-Yield Subtopics for Last-Minute Revision
- Exact spore types for all four fungal classes
- TMV: RNA virus, rod-shaped, helical coat, Ivanowsky 1892
- T.O. Diener (1971) = viroids; Prusiner (1982) = prions
- Protozoan classification by locomotion (PACS mnemonic)
- Archaebacteria: no peptidoglycan; three habitat types