Chapter at a glance
- Biotechnology deals with industrial-scale production of biopharmaceuticals and biologicals using genetically modified microbes, fungi, plants and animals.
- Three critical research areas: improved organism (catalyst), optimal engineering conditions for the catalyst, and downstream processing for purification.
- Agricultural applications include tissue culture, micro-propagation, somatic hybridisation and genetically modified crops for abiotic stress tolerance, pest resistance and enhanced nutrition.
- Bt toxin from Bacillus thuringiensis is expressed in crops (Bt cotton) to confer insect resistance; the inactive protoxin is activated in the alkaline insect gut, forming pores that cause cell lysis.
- RNA interference (RNAi) is used to silence specific nematode mRNA in transgenic plants, protecting against Meloidogyne incognitia.
- Medical applications include recombinant human insulin (chains A and B produced separately in E. coli and joined by disulphide bonds), gene therapy and molecular diagnosis by PCR and ELISA.
- Transgenic animals (>95 % mice) are produced for studying gene regulation, disease models, biological products (e.g., α-1-antitrypsin, human alpha-lactalbumin in Rosie), vaccine safety and toxicity testing.
- Ethical regulation is enforced by GEAC; biopiracy refers to unauthorised commercial use of bio-resources and traditional knowledge without compensatory payment.
Definitions and laws
- Totipotency: “This capacity to generate a whole plant from any cell/explant is called totipotency.”
- Micro-propagation: “This method of producing thousands of plants through tissue culture is called micro-propagation.”
- Somaclones: “Each of these plants will be genetically identical to the original plant from which they were grown, i.e., they are somaclones.”
- Somatic hybrids / somatic hybridisation: “These hybrids are called somatic hybrids while the process is called somatic hybridisation.”
- Genetically Modified Organisms (GMO): “Plants, bacteria, fungi and animals whose genes have been altered by manipulation are called Genetically Modified Organisms (GMO).”
- Gene therapy: “Gene therapy is a collection of methods that allows correction of a gene defect that has been diagnosed in a child/embryo. Here genes are inserted into a person’s cells and tissues to treat a disease.”
- Transgenic animals: “Animals that have had their DNA manipulated to possess and express an extra (foreign) gene are known as transgenic animals.”
- Biopiracy: “Biopiracy is the term used to refer to the use of bio-resources by multinational companies and other organisations without proper authorisation from the countries and people concerned without compensatory payment.”
(No numerical laws or SI-unit formulas appear in the chapter.)
Important diagrams and activities
- Figure 10.1 Cotton boll: (a) destroyed by bollworms; (b) a fully mature cotton boll — demonstrates damage caused by lepidopteran pests versus healthy Bt-protected boll.
- Figure 10.2 Host plant-generated dsRNA triggers protection against nematode infestation — shows RNAi-mediated silencing that prevents Meloidogyne incognitia survival in transgenic roots.
- Figure 10.3 Maturation of pro-insulin into insulin (simplified) — illustrates removal of C-peptide to obtain mature two-chain insulin linked by disulphide bridges.
- Activity: Visit a tissue culture laboratory — demonstrates explant culture, micro-propagation and production of virus-free plants from meristems.
Common misconceptions and exam pitfalls
- Bt toxin is often mistakenly thought to be active inside the bacterium; NCERT states it exists as inactive protoxin crystals that require alkaline gut pH for activation.
- Insulin cannot be taken orally because it is a protein degraded by proteases; many students overlook this when discussing recombinant insulin.
- Gene therapy for ADA deficiency is not permanent unless the gene is introduced at the embryonic stage; periodic lymphocyte infusion is required otherwise.
- PCR detects low pathogen nucleic-acid amounts by amplification, not by antigen detection (ELISA); confusing the two techniques is common.
- “Pomato” is an example of somatic hybridisation but lacks commercial traits; students sometimes present it as a successful crop.
- Biopiracy and patent issues (Basmati, turmeric, neem) must be linked specifically to lack of authorisation and compensatory payment, not to general ethical concerns.
Formula sheet
No mathematical formulas or equations are present in the chapter.