CUET UG Biology: Biotechnology - Applications of Biotechnology, Bt Crops, Biopiracy, Golden Rice

Must-Know (15–20 detailed bullets)

• Bt crops are genetically engineered to express cry genes from Bacillus thuringiensis, which code for insecticidal crystal proteins (e.g., CryIAc, CryIIAb).
• The cry genes produce protoxins that become active in the alkaline gut of lepidopteran insects like bollworms.
• Bt cotton in India expresses cry1Ac and cry2Ab genes to target cotton bollworm (Helicoverpa armigera).
• Bt toxin does not affect humans because human stomach is acidic and lacks specific receptors for the toxin.
• Bt brinjal was developed by Mahyco in collaboration with Cornell University and USAID; first GM food crop approved for cultivation in India (field trials only; commercial cultivation banned since 2010).
• Biopiracy refers to the use of bioresources or traditional knowledge by multinational companies without proper authorization or compensation (e.g., neem, turmeric, basmati).
• The case of patenting of basmati rice by Ricetec Inc. in the USA (1997) is a classic example of biopiracy.
• The Indian government challenged the basmati patent, leading to cancellation/restriction of several claims by USPTO.
• The Tasmanian bald claw disease case is not in NCERT; verify from NCERT.
• The Convention on Biological Diversity (CBD) was signed in 1992 at the Rio Earth Summit to prevent biopiracy and ensure fair benefit-sharing.
• India established the National Biodiversity Authority (NBA) in 2003 under the Biological Diversity Act, 2002.
• Golden Rice is genetically modified to produce beta-carotene (provitamin A) in the endosperm using genes psy (phytoene synthase) from daffodil (Narcissus pseudonarcissus) and crtI (carotene desaturase) from Erwinia uredovora.
• Deficiency of vitamin A causes xerophthalmia and night blindness, especially in children.
• Golden Rice aims to combat vitamin A deficiency in developing countries like India and the Philippines.
• The first field trials of Golden Rice were conducted in the Philippines; not yet approved for commercial cultivation in India.
• Biopatents grant exclusive rights to use, sell, or market a biological invention, often leading to biopiracy if traditional knowledge is exploited.
• The European Patent Office (EPO) granted a patent on wound-healing properties of turmeric in 1995, later revoked after challenge by CSIR, India.
• Use of Agrobacterium tumefaciens as a vector is common in creating Bt crops and Golden Rice.
• The cry genes are incorporated into plant genome via recombinant DNA technology using Ti plasmid.
• Bt crops reduce reliance on chemical pesticides but raise concerns about pest resistance and impact on non-target organisms.

Difficulty Level

Intermediate — Requires understanding of genetic modification techniques, real-world examples, and ethical issues; some facts are easily confused (e.g., which genes in Golden Rice, status of Bt brinjal).

Common CUET Traps (3 bullets)

• Trap: Students assume Bt toxin is harmful to humans because it kills insects.
  Avoid: Remember Bt toxin is activated only in alkaline insect guts and lacks receptors in mammals.
• Trap: Confusing Golden Rice with Bt rice; thinking it controls pests.
  Avoid: Golden Rice addresses vitamin A deficiency, not pest resistance.
• Trap: Believing Bt brinjal is currently cultivated in India.
  Avoid: Bt brinjal was approved for commercial release in 2009 but banned in 2010; only field trials allowed.

Practice MCQs (5 questions)

Q1. Which gene is used in Bt cotton to confer resistance against bollworm?
A. nif gene
B. cry1Ac
C. Bt toxin gene from E. coli
D. gus gene

Answer: B
Explanation: cry1Ac is the gene from Bacillus thuringiensis used in Bt cotton.
Why others fail: nif genes are for nitrogen fixation; gus is a reporter gene; Bt toxin is not from E. coli.

Q2. Golden Rice is enriched with which nutrient?
A. Iron
B. Vitamin D
C. Beta-carotene
D. Folic acid

Answer: C
Explanation: Golden Rice produces beta-carotene (provitamin A) in the endosperm.
Why others fail: Iron fortification is targeted in other biofortified crops like iron-rich beans, not Golden Rice.

Q3. The case of basmati rice patenting by Ricetec Inc. relates to:
A. Bioremediation
B. Biopiracy
C. Biodegradation
D. Biofortification

Answer: B
Explanation: Patenting of Indian basmati by a foreign company without benefit-sharing is biopiracy.
Why others fail: Bioremediation involves cleaning pollutants; biofortification increases nutrients; not related here.

Q4. Which of the following pairs is correctly matched regarding Golden Rice?
A. crtI – daffodil
B. psy – Erwinia uredovora
C. crtI – Erwinia uredovora
D. cry – daffodil

Answer: C
Explanation: crtI (carotene desaturase) is from Erwinia uredovora; psy is from daffodil.
Why others fail: Option A and B reverse the sources; cry is unrelated to Golden Rice.

Q5. The National Biodiversity Authority was established under which Act?
A. Environment (Protection) Act, 1986
B. Forest Conservation Act, 1980
C. Biological Diversity Act, 2002
D. Wildlife Protection Act, 1972

Answer: C
Explanation: NBA was established under the Biological Diversity Act, 2002.
Why others fail: Other acts deal with environment, forests, or wildlife, not biodiversity governance.

Last?Minute Revision (15–20 one?liners)

• Bt toxin is encoded by cry genes from Bacillus thuringiensis.
• cry genes produce protoxins activated in alkaline insect gut.
• Bt cotton targets lepidopteran pests like bollworm.
• Bt brinjal: first GM food crop in India; commercial cultivation banned since 2010.
• Biopiracy: unauthorized use of bioresources/traditional knowledge (e.g., basmati, neem).
• Basmati patent controversy: Ricetec Inc., USA, 1997.
• Turmeric wound-healing patent revoked by USPTO after CSIR challenge.
• CBD signed in 1992 at Rio Earth Summit.
• NBA established in 2003 under Biological Diversity Act, 2002.
• Golden Rice: contains psy (daffodil) + crtI (Erwinia) genes.
• Golden Rice produces beta-carotene in endosperm.
• Vitamin A deficiency causes xerophthalmia and night blindness.
• Golden Rice does not confer pest resistance.
• Bt crops use Agrobacterium or gene gun for gene transfer.
• Biopatents can lead to biopiracy if traditional knowledge is exploited.
• cry genes are inserted via Ti plasmid of Agrobacterium tumefaciens.
• Human stomach is acidic-no activation of Bt toxin.
• Non-target organisms (e.g., butterflies) may be harmed by Bt crops.
• GM crops require biosafety regulations and public acceptance.
• Mnemonic: "Bt = BioToxin for insects" – not for humans.