Section 14 — NEET-Pattern Practice Questions (Biotechnology and Its Applications)
Biotechnology and Its Applications is a compact, high-return NEET chapter — you can usually expect 2 to 4 questions from it, and they are almost always gettable if your named examples are tight. The questions sweep across the four themes of the chapter: applications in agriculture (tissue culture, GM crops, Bt toxin and the cry genes, RNAi-based pest resistance), applications in medicine (recombinant insulin, gene therapy, molecular diagnosis), transgenic animals, and the ethical issues around GM organisms and biopiracy.
This section is a focused 28-question NEET-pattern practice quiz covering the whole chapter — mostly matching-and-recall (which gene, which organism, which year, which product) with a few concept traps (protoxin vs active toxin, sense vs anti-sense RNA, active vs periodic gene therapy).
Important note: These are NEET-pattern practice questions built on the recurring core concepts of this chapter. Do not treat them as exact authenticated year-tagged papers unless each one is separately matched against an official NEET paper and year.
How to use: Treat this like a timed mock — give yourself about 25 minutes for all 28 questions. Attempt first, then read each explanation carefully. Use the recap below to spot the recurring question patterns before you begin.
Recurring NEET Hooks — Quick Recap
Most questions on this chapter fall into these repeating patterns:
1. Bt toxin and the cry genes — Bt toxin comes from the bacterium Bacillus thuringiensis. It exists as an inactive protoxin and becomes active only in the alkaline pH of the insect gut, where it binds midgut cells, makes pores, and lyses them. The toxin is coded by cry genes: cryIAc and cryIIAb control the cotton bollworm, cryIAb controls the corn borer.
2. RNA interference (RNAi) — a cellular defence in all eukaryotes; a complementary dsRNA silences a specific mRNA. Against the root nematode Meloidogyne incognita in tobacco, both sense and anti-sense RNA are introduced (via Agrobacterium) so the resulting dsRNA silences the parasite's mRNA.
3. Recombinant insulin — human insulin has two chains, A and B, joined by disulphide bridges; made in the body as a pro-hormone with an extra C peptide that is removed on maturation. Eli Lilly (1983) put the A and B chain sequences into E. coli plasmids, produced the chains separately, then joined them.
4. Gene therapy — first done in 1990 on a four-year-old girl with adenosine deaminase (ADA) deficiency (caused by deletion of the ADA gene). A functional ADA cDNA in a retroviral vector is put into her lymphocytes; because these cells are not immortal, the treatment must be repeated periodically.
5. Molecular diagnosis — PCR detects very low amounts of pathogen nucleic acid (used to detect HIV early); ELISA works on antigen-antibody interaction; a radioactive probe locates a mutated gene by hybridisation and autoradiography.
6. Transgenic animals — over 95 per cent are mice; Rosie (1997) was the first transgenic cow, giving milk enriched with human alpha-lactalbumin; alpha-1-antitrypsin is a transgenic product used to treat emphysema.
7. GM benefits and golden rice — GM crops resist pests, tolerate abiotic stress, cut post-harvest loss, and improve nutrition; golden rice is Vitamin A enriched rice.
8. Ethics — GEAC (Genetic Engineering Approval Committee) clears GM research and organisms in India; biopiracy is the use of bio-resources without authorisation or fair payment; the Basmati patent (1997, US) is the classic example.