How this Chapter is Tested in NEET
Molecular Basis of Inheritance is the single highest-yielding chapter in the NEET Biology paper - it regularly contributes several questions every year, mixing direct recall with short calculations and 'who-did-what'.
The recurring favourites are:
- DNA structure and packaging - Chargaff's rules and base-composition / length calculations, base pairing and hydrogen bonds, and histones / nucleosomes.
- The search for the genetic material - Griffith, Avery-MacLeod-McCarty, Hershey-Chase, and why DNA (vs RNA); the RNA world.
- Replication - semiconservative / Meselson-Stahl, DNA polymerase (5' to 3'), leading vs lagging, Okazaki, ligase.
- Transcription - the transcription unit, RNA polymerase I/II/III, sigma / rho, and splicing, capping, tailing.
- Genetic code and translation - triplet, degenerate, universal, AUG/stop codons, tRNA the adaptor, rRNA the ribozyme.
- Regulation - the lac operon (structural genes, repressor, inducer, and 'what happens if…') and its logic.
- HGP and DNA fingerprinting - key numbers, chromosome 1 / Y, ESTs, and VNTR polymorphism and the fingerprinting steps.
The set below combines genuine NEET previous-year questions with a few exam-pattern questions. Several are calculations - set up the numbers rather than guessing.
Strategy: for a base-composition or length question, use A=T, G=C and 0.34 nm/bp; for an experiment question, fix the scientist-to-discovery link; for the lac operon, trace the repressor -> operator -> RNA polymerase logic step by step.