Introduction to Biotechnology Chapter Notes | Biotechnology for Class 11 - NEET PDF Download

Introduction

• Natural sciences have been applied to develop technologies for human welfare and comfort, enhancing the value of human lives.
• Research in physics and chemistry has led to the growth of engineering and technology industries.
• Biotechnology is a broad area of biology that has expanded into fields such as genetics, immunology, agriculture, and genomics.
• The term "biotechnology" combines "bio" (biological systems or processes) and "technology" (methods, systems, and devices used to create useful products).
• Biotechnology involves using living cells and/or biological molecules to generate products beneficial to mankind.
• Modern biotechnology is multidisciplinary, integrating fields like Cell and Molecular Biology, Microbiology, Genetics, Anatomy and Physiology, Biochemistry, Computer Science, and Recombinant DNA technology (rDNA).

Historical Perspectives

• The term "biotechnology" was coined by Hungarian scientist Karl Ereky in 1917 in his book, describing the transformation of plants and animals into useful products.
• Ancient biotechnology began around 10,000 years ago in the Paleolithic era with the cultivation of crops like wheat and barley.
• Civilizations in the Sahara region domesticated sheep, goats, and cattle, and were skilled in hunting and using fire.
• Early farmers collected seeds of wild plants for cultivation and domesticated animals through selective breeding.
• Ancient Egyptian farmers conserved plant stocks, an early form of germplasm conservation.
• Fermentation technology, used for producing bread, cheese, wine, and beer, is a classical example of medieval biotechnology.
• In ancient India, traditional knowledge included making fermented foods like dahi, idli, and kinema, and beverages using local biological resources.
• Fermentation is a microbial process involving enzymatically controlled conversion of organic compounds.
• Fermented dough was discovered accidentally when unbaked dough underwent yeast fermentation (e.g., Saccharomyces winlocki).
• Egypt and Mesopotamia exported bread to Greece and Rome, and Romans discovered Baker’s Yeast, revolutionizing bread-making.
• By 4000 B.C., the Chinese used fermentation for soy sauces and fermented vegetables.
• Egyptians produced vinegar by 2000 B.C. through preserving crushed dates.
• Prehistoric East and Europe preserved animal foods by drying, smoking, and pickling in brine.
• Beer production may have started between 6000 and 5000 B.C. using grains like sorghum, corn, rice, millet, and wheat.
• Brewing was considered an art until the 14th century, with no knowledge of its microbial basis.
• Wine was likely discovered accidentally when grape juice was contaminated with yeast and microbes.
• Between 1850s and 1860s, Louis Pasteur established that yeast and microbes were responsible for fermentation.
• The 19th century saw increased production of fermentation-based products like glycerol, acetone, butanol, lactic acid, and citric acid.
• Industrial fermentation began during World War I to produce glycerol for explosives in Germany.
• By the 1940s, improvements in sterility, aeration, product isolation, and purification were made.
• World War II led to the invention of modern fermenters (bioreactors) for mass production of penicillin.
• Today, antibiotics, amino acids, hormones, pigments, and enzymes are produced in controlled industrial bioreactors.
• The first compound microscope, made by Zacharias Janssen in 1590, magnified 3x–9x, enabling observation of microscopic entities.
• In 1665, Robert Hooke examined cork and described rectangular components as "cellulae" (small chambers).
• In 1676, Antonie van Leeuwenhoek observed living organisms in pond water, calling them "animalcules."
• In the 18th century, Matthias Schleiden and Theodor Schwann developed the cell theory, stating all plant and animal tissues are composed of cells.
• In 1858, Rudolf Virchow concluded that all cells arise from pre-existing cells, establishing the cell as the basic unit of life.
• Between 1850 and 1880, Pasteur developed pasteurization and disproved spontaneous generation.
• In 1896, Eduard Buchner converted sugar to ethyl alcohol using yeast extracts, showing biochemical transformations without cells.
• By the 1920s and 1930s, biochemical reactions of major metabolic pathways were established.
• In 1857, Gregor Mendel began experiments on pea plants, laying the foundation for genetics and heredity.
• In 1869, Johann Friedrich Miescher isolated "nuclein" (nucleic acids) from white blood cell nuclei.
• In 1882, Walter Flemming described thread-like bodies (chromosomes) during cell division.
• In 1952, Alfred Hershey and Martha Chase identified DNA as the genetic material.
• In 1953, James Watson and Francis Crick proposed the double helical structure of DNA.
• Subsequent experiments clarified how genes function, including DNA replication and repair enzymes.

Applications of Modern Biotechnology

• Modern biotechnology uses rDNA technology to cut, join, and transfer DNA into new hosts, conferring novel properties.
• rDNA technology has revolutionized biotechnology with precision and efficiency, impacting medicine, agriculture, animal science, and environmental science.
• Biotechnology includes Blue (marine/freshwater organisms), Green (environment-friendly plant solutions), Red (medical/pharmaceutical), and White (industrial processes).

Medicine and Health Care

• Biotechnology aids in developing diagnostic tools and kits to detect molecules and cellular components in diseased conditions.
• rDNA technology, bioinformatics, modern instrumentation, and bioprocess technologies enable prediction and synthesis of synthetic drug analogs.
• Vaccines and gene therapy are key applications in medicine.
• rDNA technology produces therapeutic molecules like biopharmaceuticals in microorganisms, transgenic plants, or animals.
• Human insulin, used for diabetes treatment, is produced in Escherichia coli and Saccharomyces cerevisiae.
• Human growth hormone is produced in microbial host systems via rDNA technology.
• Blood anticoagulant is produced in the milk of transgenic goats, approved by the FDA.
• Scientists are developing drugs for hepatitis, cancer, and heart diseases, major causes of mortality.
• Gene therapy delivers genes to treat diseases caused by genetic defects (e.g., cystic fibrosis, thalassemia, Parkinson’s disease).
• Conceptualized in 1972, the first unsuccessful gene therapy attempt was by Martin Cline in 1980 for β-thalassemia.
• In 1990, Ashanthi De Silva was successfully treated for Adenosine Deaminase Severe Combined Immunodeficiency (ADA-SCID).
• China approved Gendicine in 2003 for cancer treatment, and Russia approved Neovasculgen in 2011 for peripheral artery disease.
• Genetic testing identifies defects in chromosomes, genes, or protein expression to determine disease risk.
• Tests for phenylketonuria (lacking enzyme to metabolize phenylalanine) and congenital hypothyroidism (thyroid disorder) have been developed.

Crop Production and Agriculture

• Biotechnology revolutionizes agriculture by enabling genetic manipulation for stress resistance and improved food quality.
• Five major traits for crop improvement: insect resistance, herbicide resistance, virus resistance, delayed fruit ripening, and nutritional enhancement.
• Transgenic plants (GMOs) incorporate useful genes for stable expression of desired traits.
• Virus-resistant plants overproduce viral coat protein genes to prevent viral reproduction (e.g., Papaya Ring Spot Virus, Cucumber Mosaic Virus).
• Insect-resistant plants, like Bt cotton, express Cry 1A(b) toxin from Bacillus thuringiensis, targeting moths, butterflies, and beetles.
• Bt toxin genes are expressed in brinjal, corn, potato, soybean, tomato, and tobacco.
• Abiotic stress-resistant plants include tobacco with glycerol-1-phosphate acyl-transferase enzyme for chilling resistance.
• Roundup-ready soybeans are resistant to glyphosate herbicide, allowing selective weed control.
• Flavr Savr tomatoes have extended shelf life due to delayed ripening.
• Golden Rice has high beta-carotene content for vitamin A production, appearing golden due to overexpression.
• Plant tissue culture enables clonal propagation of plants difficult to breed conventionally.
• Haploid generation through anther/pollen culture aids crop improvement.
• Plant cell culture preserves horticultural crops with recalcitrant seeds or perennial crops.
• Transgenic plants express therapeutic molecules, like antibiotics in stock feed plants (e.g., bamboo, wheat grass) for animal use.
• Edible vaccines are produced in transgenic plants (e.g., potato-based vaccines for measles, cholera, Norfolk virus).
• Biofuels are produced biologically from plants or agricultural wastes via thermal, chemical, or biochemical conversion.
• Bioethanol is produced by fermenting sugars and starches; biodiesel uses oils or fats (e.g., soy, rapeseed, Jatropha).
• Sweet sorghum is investigated for biofuel in drylands, using minimal water.
• Jatropha curcas seeds are a viable source of biofuel feedstock oil.

Food Processing

• Biotechnology improves edibility, texture, storage, and shelf life of food, prevents mycotoxin production, and delays nutritional degradation.
• One-third of the world’s diet consists of fermented foods.
• Protein-engineered microbial enzymes enhance fermentation and are produced commercially in industrial fermenters.
• Industrial-scale production of fermented foods like cheese, yoghurt, probiotics, and buttermilk improves taste, nutrition, and shelf life.

Environmental Protection

• Environmental biotechnology studies the natural environment to develop green technology and remediate contaminated environments.
• Eco-toxicological biomarkers indicate biological responses to environmental or chemical stimuli.
• The lux gene in E. coli acts as a biosensor for detecting mercury contamination.
• Bioremediation uses natural sources to convert hazardous substances into nontoxic compounds.
• Genetic engineering creates organisms for bioremediation, like E. coli with biphenyl dioxygenase to degrade polychlorinated biphenyl (PCB).
• Hyper-accumulator plants (e.g., Brassica napus, Helianthus annus) remove heavy metals (cadmium, mercury, lead) from contaminated soils.
• Environmental biotechnology provides sustainable solutions through genomics, proteomics, bioinformatics, and sequencing.

Biotechnology in India: Academic Prospects and Industrial Scenario

• The Department of Biotechnology (DBT), established in 1986 from the National Biotechnology Board (1982), supports human resource development.
• DBT offers scholarships, DBT-JRF for doctoral research, and DBT research associateships for postdoctoral studies.
• Early biotech firms include Serum Institute of India (1960s) and Biocon (1978).
• DBT supports postgraduate programs in Agricultural Biotechnology, Marine Biotechnology, Neuroscience, Industrial Biotechnology, and Environmental Biotechnology.
• Certificate and diploma courses in biotechnology are offered by premier institutes.
• DBT-established research institutes include CDFD (Hyderabad), IBSD (Imphal), and NII (New Delhi).
• The Indian biotechnology industry is among the top 12 globally and third in Asia-Pacific for industrial biotechnology infrastructure.
• Industry segments: Bio-pharma, Bio-services, Bio-agri, Bio-industrial, and Bio-informatics.
• India has the fourth largest area of genetically modified crops.
• Bio-pharma focuses on vaccine manufacturing, diagnostics, and therapeutics, producing recombinant Hepatitis B vaccine, insulin, and erythropoietin.
• India is the world’s largest producer of recombinant Hepatitis B vaccine.
• Bharat Biotech launched ROTAVAC for rotavirus diarrhea and Covaxin for Covid-19.
• Vaccines are exported to over 140 countries, including UNICEF and PAHO.
• Major vaccine producers: Serum Institute, Bharat Serum, Panacea Biotec.
• Therapeutics include stem cell research, monoclonal antibodies, and cell-based therapies.
• India is the largest producer of statins and immunosuppressants, supplying 80% of global antiretroviral drugs for AIDS.
• Agriculture features Bt cotton (45% market share), transgenic rice, and GM maize with high protein and provitamin A.
• Bio-services include contract research organizations like GVK Bio and Quintiles.
• Biotech companies: Biocon, Dr. Reddy’s, Serum Institute, Bharat Biotech.
• Biotech parks: Bangalore Biotech Park, ICICI Knowledge Park (Hyderabad), Ticel Bio Park (Chennai).
• In 2016, Sun Pharma and ICGEB signed an MOU for a dengue vaccine.