Revision: Biotechnology >> Biotechnology and Its Application Biology Science (English Medium) Class 12 CBSE

The technique of bringing about improvements in living organisms by genetic modifications and hybridization, for the welfare of human beings is known as ‘Biotechnology’.

A transgenic animal is an animal whose genome has been artificially modified to contain one or more genes from another species.

Bioethics are a set of standards that may be used to regulate our activities in relation to the biological world.

Bioethics is the branch of ethics that deals with moral principles and issues arising from advances in biology, medicine, and life sciences.

The soil bacterium Bacillus thuringiensis (Bt) produces an insecticidal protein called 'Bt toxin'.

Bt cotton is a transgenic cotton variety that contains one or more genes from Bacillus thuringiensis and therefore produces an insecticidal protein toxic to certain insect pests.

'Biopiracy' is defined as 'the theft of various natural products and then selling them by getting a patent without giving any benefits or compensation back to the host country’.

or

It is an unauthorised misappropriation of any biological resource and indigenous knowledge.

• Biotechnology, a term coined by Karl Ereky in 1919, is the use of biological systems and genetic modifications to develop products and services for human welfare.
• Traditional biotechnology relies on small-scale, natural processes like fermentation (e.g., producing curd and wine), whereas modern biotechnology operates on a large scale.
• Modern biotechnology is fundamentally driven by two core techniques: genetic engineering (the targeted alteration of DNA and RNA) and bioprocess engineering.
• The field experienced a major breakthrough with the development of recombinant DNA technology by Cohen and Boyer in 1973.
• By integrating disciplines such as molecular biology and biochemistry, biotechnology enables crucial applications in both medicine (antibiotics, vaccines, insulin) and agriculture (high-yield, disease-resistant crops).

• While the Green Revolution significantly increased food production using agrochemicals, biotechnology offers a sustainable alternative to overcome yield limitations and chemical pollution.
• Tissue culture enables micropropagation, allowing for the rapid, large-scale production of genetically identical and disease-free plants from small tissue samples.
• Somatic hybridisation allows scientists to fuse the cell-wall-free protoplasts of two distinct plant varieties to create new hybrids with combined desirable traits.
• Genetically modified crops are engineered to possess highly beneficial characteristics, including enhanced nutritional value and increased tolerance to harsh environmental stresses.
• Agricultural biotechnology drastically reduces the reliance on harmful chemical pesticides by developing inherently pest-resistant plants, such as Bt cotton.

• Recombinant DNA technology allows for the mass production of safe therapeutic proteins, eliminating the allergic reactions associated with earlier animal-derived medicines.
• Genetically engineered human insulin is produced by separately synthesising the A and B chains in E. coli and linking them with disulphide bonds.
• Biotechnology facilitates the development of recombinant subunit vaccines, which use specific pathogen antigens to safely stimulate the immune system.
• Transgenic plants can be engineered to produce cost-effective edible vaccines that deliver injection-free mucosal and systemic immunity upon consumption.
• Gene therapy treats genetic disorders like ADA deficiency (SCID) by using retroviral vectors to insert a functional gene into a patient's extracted lymphocytes.
• Patients receiving gene therapy for ADA deficiency require periodic infusions of genetically corrected lymphocytes because these cells have a limited lifespan.
• Polymerase Chain Reaction (PCR) is a highly sensitive molecular diagnostic tool that amplifies trace amounts of DNA or RNA to detect diseases before clinical symptoms arise.
• Molecular diagnostics also use ELISA for mass screening via antigen-antibody reactions and DNA probes to detect specific genetic mutations through hybridisation.

• Transgenic animals have artificially modified genomes containing specific foreign genes from other species.
• They are produced by isolating a desired gene, inserting it into a host embryo, and growing it into a complete animal expressing the new trait.
• They serve as essential living models for studying normal physiology, understanding complex diseases, and testing the safety of vaccines and chemicals.
• They function as biological factories for therapeutic products, such as "Rosie", the first transgenic cow that produced human protein-enriched milk.
• Mice are the most widely used models in disease research, while other animals such as sheep, pigs, and fish are utilised for medical and agricultural advancements.

• Bioethics sets moral standards to safely regulate biotechnology and prevent the misuse of biological resources.
• Major ethical concerns focus on preventing animal suffering in research and avoiding the ecological risks of cross-species gene transfer.
• Biosafety protocols are essential to protect human health and the environment from the unpredictable effects of genetically modified organisms (GMOs).
• The Genetic Engineering Appraisal Committee (GEAC) strictly evaluates and regulates the safe release of genetically engineered products into the environment.

• Bt cotton is a transgenic cotton crop containing gene(s) from the soil bacterium Bacillus thuringiensis, enabling it to produce an insecticidal protein.
• This protein, known as Bt toxin, is initially produced in an inactive form called a protoxin.
• The protoxin becomes activated only in the alkaline gut environment of susceptible insects such as bollworms.
• The active toxin binds to midgut epithelial cells, causing pore formation, cell swelling, and eventual cell lysis leading to insect death.
• Different cry genes (cryIAc, cryIIAb, and cryIAb) target different pests, with cryIAc and cryIIAb controlling cotton bollworm and cryIAb controlling corn borer.
• Bt cotton reduces dependence on chemical insecticides and offers targeted pest resistance, though insects may eventually develop resistance to the toxin over time.

• Nematode pests like Meloidogyne incognita damage plant roots, reduce crop yield, and require bioengineering for resistance.
• RNA interference (RNAi) is used to silence pest genes by preventing translation of nematode mRNA.
• In transgenic tobacco, both sense and antisense RNA are produced, forming dsRNA that triggers post-transcriptional gene silencing.
• Agrobacterium tumefaciens is used as a vector to transfer nematode-specific genes, making plants pest-resistant.

• Nematode-specific genes are introduced into the host plant using an Agrobacterium vector to synthesise complementary sense and antisense RNA.
• These complementary RNA strands pair together within the host cells to form a double-stranded RNA (dsRNA) molecule.
• Once the nematode ingests the dsRNA, an enzyme called dicer cleaves it into smaller fragments known as small interfering RNAs (siRNA).
• The siRNA binds with the Argonaute protein to form the RNA-induced silencing complex (RISC), where it unwinds into a single active strand.
• This single-stranded siRNA guides the RISC to bind specifically to the complementary target mRNA produced by the nematode.
• The complex cleaves the target mRNA, effectively blocking its translation into protein and neutralising the parasite to protect the plant.

• Biopiracy is the unauthorised use or patenting of biological resources and traditional knowledge without giving compensation to the original owners.
• It mainly occurs when developed countries exploit the rich biodiversity and traditional knowledge of developing countries.
• Traditional knowledge includes information about agriculture, medicines, and conservation practices passed through generations.
• Biopiracy harms indigenous communities by denying them rights, benefits, and recognition for their knowledge.
• Common examples include the patenting of neem, basmati rice, and turmeric (haldi) by foreign companies, which were later challenged and revoked.