Chapter 12: Biotechnology and Its Applications

Q1. What is Bt cotton? How does it protect against bollworms?

Solution

Bt cotton contains the cry gene from Bacillus thuringiensis that produces the Cry protein (Bt toxin).

Mechanism: When bollworm eats Bt cotton, the alkaline gut activates the toxin, which binds to gut receptors, creating pores, leading to insect death.

Q2. What is gene therapy? Give an example.

Solution

Gene therapy is the introduction of a functional gene to correct a genetic disorder.

Example: ADA deficiency - Adenosine deaminase gene is introduced into patient's cells to treat SCID (Severe Combined Immunodeficiency).

Q3. What are transgenic animals? Name one example and its use.

Solution

Transgenic: Animals with foreign genes inserted into their genome
Example: Transgenic cow (Rosie) - produces human alpha-lactalbumin in milk, more nutritionally balanced

Q4. What are molecular diagnosis techniques?

Solution

1. PCR (amplify pathogen DNA)
2. ELISA (detect antigens/antibodies)
3. DNA probes (detect specific sequences)
4. Western blotting (detect proteins)

Q5. What is Golden Rice?

Solution

Development: (1) Genes for beta-carotene pathway introduced (2) Expressed in endosperm (3) Rice appears golden yellow (4) Addresses Vitamin A deficiency

Q6. What is bioremediation? Give examples.

Solution

Examples: (1) Pseudomonas putida - degrades hydrocarbons (2) Alcanivorax borkumensis - degrades petroleum (3) Fungi (Phanerochaete) - degrades toxic chemicals

Q7. What are the applications of transgenic plants in agriculture?

Solution

1. Insect resistance (Bt cotton, Bt corn)
2. Herbicide tolerance (Roundup Ready soybean)
3. Disease resistance (virus-resistant papaya)
4. Improved nutritional quality (Golden Rice)
5. Extended shelf life (Flavr Savr tomato)

Q8. What is ELISA? How does it work?

Solution

Steps: (1) Antigen coated on plate (2) Primary antibody added (3) Enzyme-linked secondary antibody (4) Substrate added (5) Color change indicates antigen
Used for: HIV, pregnancy test, cancer markers

Q9. What are the potential risks of GMOs?

Solution

1. Gene flow to wild relatives
2. Development of superweeds
3. Harm to non-target organisms
4. Allergenicity
5. Loss of biodiversity

Q10. What are biosafety guidelines for GMOs?

Solution

1. Containment during research (BSL levels)
2. Restricted field trials
3. Environmental risk assessment
4. Labeling of GM products
5. Regulatory approval before release

Q11. What are the applications of transgenic animals in medicine?

Solution

1. Production of therapeutic proteins
2. Study of disease mechanisms
3. Drug testing and toxicology
4. Organ transplantation research
5. Vaccine production

Q12. What is RNA interference (RNAi)?

Solution

Mechanism: (1) dsRNA enters cell (2) Dicer cuts it into siRNA (3) siRNA binds RISC complex (4) Target mRNA degraded
Uses: Pest resistance, gene function studies

Q13. What is the difference between somatic and germline gene therapy?

Solution

Somatic: Modifies body cells, not inherited (legal, current approach)
Germline: Modifies reproductive cells, inherited by offspring (ethical concerns, not approved)

Q14. What is the importance of patenting in biotechnology?

Solution

1. Protects intellectual property
2. Encourages research and development
3. Provides financial incentive
4. Ensures product quality
5. Issues: Biopiracy, ethics of gene patenting

Q15. What are the ethical issues related to biotechnology?

Solution

1. Safety concerns with GMOs
2. Patenting of life forms
3. Biopiracy and bioprospecting
4. Human cloning ethics
5. Ownership of genetic information

← Chapter 11: Biotechnology: Principles and Processes Chapter 13: Organisms and Populations →

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