Lesson-30.pdf). Content covers sections 30.1–30.9.At home we make yoghurt, bread, idli and dosa with bacteria and fungi. Brewers use yeast for beer; penicillin comes from fungi. This NIOS Module 5 lesson scales those ideas: fermentation industries, dairy, antibiotics, vaccines, vitamins, biogas, genetic engineering, recombinant DNA, transgenics, bioremediation and gene therapy. After this lesson you should define biotechnology; list industrial microbes and products; outline alcohol, yoghurt and biogas production; explain antibiotics and vaccine generations; describe rDNA tools and steps; define transgenic organisms; and compare approaches to gene therapy.
Biotechnology is the industrial application of living organisms and their biological processes — biochemistry, microbiology and genetic engineering — to make best use of microorganisms (and other cells) for mankind. Applications span health and medicine, environment, agriculture, food and drinks, and manufacturing.
Biotechnology supports study of infectious diseases (for example SARS and influenza) and development of better pharmaceuticals. Microorganisms produce antibiotics and vaccines: Bacillus polymyxa yields polymyxin B (urinary tract infections); Penicillium notatum yields penicillin (pneumonia and many bacterial infections). Gene therapy aims to replace a faulty gene with a normal copy for disorders such as SCID and thalassaemia, and may help some heart diseases. In forensics, DNA fingerprinting speeds identification.
Bioremediation uses living organisms — natural or genetically modified bacteria, fungi and enzymes — to break down toxic substances. Agriculture gains disease-resistant, herbicide-tolerant and insecticide-resistant crops and better livestock feed plants. Pest genetics can be altered so pests become sterile. Bio-processing grows plants that yield compounds for detergents, paints, lubricants and plastics. Food processing, preservation, and seedless fruits are biotech products. Industry uses microbes for cheese, yoghurt, alcohol and food additives.
Important industrial microbes: yeasts (fungi), moulds (fungi), bacteria, and filamentous bacteria (actinomycetes). Products include alcohol beverages, yoghurt, proteins, antibiotics and monoclonal antibodies, vitamins, steroids, enzymes and biogas. Gene manipulation also uses cultured mammalian cells and hybridomas (fusion of cells of different species).
Fermentation converts carbohydrates such as sugar into alcohol. Yeast enzymes drive: glucose → ethyl alcohol + carbon dioxide + ATP. It is energy-yielding. Louis Pasteur showed Saccharomyces cerevisiae fermentation yields beer and related products. Bakers use yeast to leaven dough; yeast grown on molasses is packed for bakery use.
Brewer’s yeast ferments sugars; the carbohydrate source gives flavour. Wine comes from grape sugars (glucose and fructose) fermented by S. cerevisiae to CO₂ and ethanol in large bioreactors. Barley malt yields beer.
Industrial fermentation steps: (i) sterilise fermenter and nutrient medium by steam under pressure (autoclave); (ii) select the correct yeast strain; (iii) inoculate — either as a surface layer (support growth system) or suspended cells/mycelia in liquid (suspended growth system); (iv) maintain temperature, pH, oxygen and CO₂; (v) stir and ferment; (vi) yeast enzymes ferment sugar; (vii) harvest product. Wine path: grape pressing → remove contaminants → sterilise → add yeast → ferment → remove excess yeast → age bouquet → bottle. Other yeast alcohols include butanol and glycerol; specific bacteria yield lactic acid and acetic acid (vinegar). Spent yeast extract is animal feed and vitamin-rich.
At home a spoon of yoghurt starter sets milk because Lactobacillus releases milk-curdling enzymes. Commercially, rennet (rennin from calf stomach) was used; bacterial starters remain central. When milk curdles, protein casein separates from liquid whey. Lactobacillus converts lactose to lactic acid, lowers pH, sours and preserves the product. Butter forms by churning sour milk so fat globules clump. Starters may include Streptococcus cremoris and Leuconostoc.
Textbook dairy table: yoghurt uses Streptococcus thermophilus and Lactobacillus bulgaricus on low- or non-fat milk with stabilisers such as gelatin. Butter uses Lactococcus lactis: cream is incubated to desired acidity, then churned, washed and salted.
In 1928 Alexander Fleming saw one microbe inhibit another. In 1942 Selman Waksman coined antibiotic (anti = opposed, biotic = living). An antibiotic is a substance produced by a microorganism (bacteria or fungi) that inhibits growth of another microbe. Antibiotics are small molecules (molecular weight usually under about 2000 Da), not enzymes. They interfere with vital metabolic steps of pathogens so growth and reproduction stop.
Broad-spectrum antibiotics (for example chloramphenicol, erythromycin, tetracycline from Streptomyces) act against more than one kind of pathogen. Narrow-spectrum antibiotics such as streptomycin and penicillin act against fewer pathogens. Drawbacks: allergy in some people; pathogens can mutate and become resistant. Major sources: tetracyclines from Streptomyces sp.; chloramphenicol from S. venezuelae; streptomycin and cycloheximide from S. griseus; cephalosporin from Cephalosporium acremonium; penicillin from Penicillium chrysogenum.
In 1790 Edward Jenner linked cowpox exposure in milkmaids to smallpox protection. He inoculated a boy with cowpox then smallpox; the boy stayed free of smallpox. Weakened (attenuated) germs can train immunity without full disease — the idea of vaccine (from Latin vacca, cow) and vaccination.
First-generation vaccines use attenuated disease-causing organisms. Second-generation vaccines use genetic engineering / recombinant DNA (examples: hepatitis B, herpes). Third-generation vaccines are synthesised chemically.
Vitamins are needed in tiny amounts for metabolism and can be made biotechnologically. Vitamin C was first produced by bacterial fermentation. B₁₂ (cyanocobalamin) production involves propionic bacteria; B₂ (riboflavin) yield can rise hundreds-fold with microbes versus natural plant/yeast sources alone.
Biogas is a renewable fuel that can spare coal, kerosene and petrol. Organic waste including cow dung (lignocellulose-rich) is fermented anaerobically by methanogenic bacteria to methane (CH₄) and CO₂. Dung goes into a digester/fermenter; gas stores above slurry; slurry is excellent manure. Conditions: no free oxygen; pH near neutral (~6.8–7.6); methanogens present. Advantages: cooking and lighting fuel; manure by-product; cheaper than household LPG in many settings.
Genes are DNA nucleotide sequences that run the body “machine.” Genetic engineering manipulates genetic material: replace genes or products, copy genes, store them in gene libraries. Disorders such as diabetes (insulin gene problem), thalassaemia (haemoglobin gene) and sickle-cell anaemia (faulty haemoglobin gene) motivate engineered DNA copies for therapy and research. Bacteria can be programmed as factories for enzymes, hormones and antibodies; engineered strains can degrade pollutants.
Genetic engineering builds and uses new DNA engineered by recombinant DNA techniques. Recombinant DNA means cutting DNA and inserting a desired foreign segment; the recombined DNA is copied in bacterial cells and stored. Multiple copies are cloned DNA or cloned genes. A clone is a group of genetically identical cells descended from one cell. Causing genetic change by artificial DNA manipulation is genetic engineering; cloning produces genetically identical individuals or genetic material from a single cell.
Two bacterial discoveries enabled rDNA: (i) plasmids — extra-chromosomal DNA that replicates with the bacterium and can carry foreign DNA as vectors; (ii) restriction enzymes that cut DNA at specific sites.
rDNA is “cut and paste.” Five requirements: (1) cell culture with the desired gene; (2) restriction endonuclease — molecular scissors recognising usually 4–6 base sequences, cutting to release restriction fragments with sticky ends; (3) plasmids cut with the same enzyme; (4) DNA ligase — molecular glue joining sticky ends; (5) host bacteria. Steps: select enzyme → culture cells → cut out gene fragment → cut matching plasmid → ligate foreign DNA into plasmid (recombinant plasmid / clonal vector; bacteriophages also work as vectors) → introduce into competent host cells → bacteria divide; plasmids replicate → millions of cells in hours → purify identical DNA copies into a DNA library.
Therapeutic proteins from cloned human genes: insulin (diabetes — first commercial rDNA success 1982), growth hormone (pituitary dwarfism), erythropoietin (anaemia), interferons (viral infections), interleukin-2 (cancer), clotting factors VIII and IX (haemophilia A and B), monoclonal antibodies, tissue plasminogen activator (heart attack). Earlier, growth hormone was scarce and expensive from animal glands; rDNA scaled production.
Enzymes from clones: proteases (detergents, meat tenderisers), amylases (beer, bread, textiles), glucoisomerases (corn syrup for soft drinks). Enzymes are fragile and may be entrapped in gels or artificial cells. Novel antibiotics and bioengineered vaccines (rabies, hepatitis B — antigen gene in plasmid, protein harvested for vaccine) also flow from this toolbox.
A transgene is a foreign gene; a transgenic organism carries it. Uses: better agricultural yield and traits; valuable products; research on gene expression.
Animal methods: (i) microinjection of foreign DNA into male pronuclei of fertilised eggs (collect oocytes → mature and fertilise in vitro → centrifuge yolk if needed → inject hundreds to thousands of gene copies → culture embryos → implant in foster mother → screen offspring); (ii) retroviral vectors infecting pre-implantation embryos.
Transgenic plants often use soil bacterium Agrobacterium tumefaciens, which has a natural Ti plasmid that causes plant galls. Gall genes can be removed and replaced with desired genes; the plasmid transforms plant cells and foreign genes express. Examples: worm-resistant cotton; drought- and pesticide-tolerant corn and soybean; potato and tobacco engineered for serum albumin (useful in burns and fluid replacement).
Transgenic animals: mice with rat growth hormone gene grew larger; goats with human tPA gene secrete clot-dissolving factor in milk for thrombosis and stroke; livestock can make drugs cheaper than huge bacterial fermenters; Chinese hamster ovary cells produce clotting factor VIII, reducing reliance on human blood and AIDS risk.
Bioremediation: engineered bacteria break toxic pollutants into harmless compounds (example: mercury-resistant bacteria convert metallic mercury to nontoxic forms).
Genetic defects cause sickle-cell anaemia, haemophilia, SCID, colour blindness and many other disorders — thousands of affected births daily in large populations. Genes control enzyme synthesis and timing; defective genes arise by inheritance (haemophilia, sickle cell, colour blindness) or new mutation (for example some albinism). Consequences: toxic metabolite build-up or missing essential compounds.
Single-gene defect map (exam table): SCID — missing adenosine deaminase → low T and B cells, loss of immunity; haemophilia — missing factor VIII → bleeding; sickle-cell — defective β-globin → organ damage; PKU — phenylalanine accumulates → mental retardation and pigmentation issues.
Gene therapy gives healthy genes to replace defective ones or enhance existing gene action so the cell’s protein machinery makes the needed product. Two approaches: somatic (body cells of one tissue/organ; not inherited by children) and germ-line (gametes/zygote — would pass to next generation; not currently practised in humans because of risk of unforeseen traits).
Ex-vivo: take patient’s cells → culture → insert remedial gene (often via retrovirus) → test → transfuse back (no immune rejection of self cells). Bone-marrow stem cells can repopulate blood lineages. Targets: SCID, sickle cell, thalassaemia, some tumours.
In-vivo: deliver remedial gene directly into tissue, often with weakened adenovirus that integrates in a tissue-specific way in dividing cells. Potential: cancer, Alzheimer’s, Parkinson’s.
Antisense: introduce nucleic acid complementary to target mRNA so translation of an over-produced protein falls. Useful when too much product harms the cell (some cancers, e.g. trials for glioma); related idea used in long-shelf-life tomato (Flavr Savr-type antisense of ripening enzymes).
Somatic therapy is early-stage for AIDS, haemophilia, atherosclerosis, leukaemia, lung cancer, SCID and others. Germ-line therapy is avoided. Limitations: somatic fixes do not pass to offspring; random DNA integration may disrupt normal genes or promote cancer; strict animal safety standards; only single-gene defects with cloned normal genes are realistic targets. Therapy is expensive and available in few centres.
Define biotechnology and name five application areas. List industrial microbes and products. Write the fermentation equation and name S. cerevisiae uses. State autoclave sterilisation and two inoculation systems. Name yoghurt bacteria and casein/whey idea. Define antibiotic; Fleming and Waksman; broad vs narrow; five sources. Three vaccine generations. Vitamin C first by fermentation. Biogas conditions and methanogens. Define genetic engineering, clone, recombinant DNA. Five rDNA tools and ordered steps. Insulin 1982; protein and enzyme tables. Transgene vs transgenic; Ti plasmid; microinjection; bioremediation. Gene therapy definition; SCID enzyme; somatic vs germ-line; ex-vivo, in-vivo, antisense; four limitations.
Biotechnology is not only genetic engineering: classical fermentation for food and drink is biotechnology too. When you write “industrial application of living organisms,” include both traditional microbes and modern rDNA. Hybridomas matter for monoclonal antibodies in diagnosis and therapy. Support growth versus suspended growth is a favourite short note: surface film versus cells floating in liquid medium.
Wine process detail scores marks: pressing, contaminant control, sterilisation, yeast addition, fermentation, yeast removal, aging bouquet, bottling. Link dairy souring to lactic acid and preservation — same logic as pickling acidity. Antibiotics are not enzymes and are small molecules; resistance and allergy explain why infectious disease still exists despite “wonder drugs.”
Vaccine generations: first = attenuated live or related mild organism (Jenner’s cowpox logic); second = recombinant antigen protein; third = fully synthetic. Biogas digesters need anaerobic methanogens and neutral pH — oxygen kills the process. Plasmid vectors and bacteriophages both carry foreign DNA; sticky ends from the same restriction enzyme let ligase join insert and vector. Molecular scissors and molecular glue are standard exam phrases.
Therapeutic protein table: insulin, GH, EPO, interferons, IL-2, factors VIII/IX, mAbs, tPA — match each to disease. Enzymes: protease, amylase, glucoisomerase uses. Transgenic goats secreting tPA in milk and factor VIII from hamster cells show “pharming” and cell culture routes. Agrobacterium is a natural genetic engineer of plants via Ti; remove tumour genes, insert cargo genes.
Gene therapy pathway diagrams: normal multistep enzyme chain versus blocked path when one gene fails (substrate piles up, end product missing). Ex-vivo uses cultured self cells and retroviral integration into stem cells for lasting supply. In-vivo uses adenovirus for direct delivery. Antisense blocks mRNA, not the gene sequence itself. Always state germ-line is not current clinical practice and why random integration is dangerous.
Broad-spectrum versus narrow-spectrum antibiotics: many pathogens versus few. First versus second versus third generation vaccines: attenuated germs versus rDNA products versus chemical synthesis. Support versus suspended inoculation: surface layer versus liquid suspension. Restriction enzyme versus ligase: cut versus join. Plasmid versus chromosomal DNA: extra-chromosomal mobile vector versus main genome. Transgenic plant Ti method versus animal microinjection: bacterial plant vector versus egg pronucleus injection. Somatic versus germ-line gene therapy: one person fixed versus heritable change. Ex-vivo versus in-vivo: cells treated outside then returned versus gene delivered inside the body. Marasmus-style “deficit” is not this lesson — here the parallel extremes are antibiotic cure versus resistance, and gene correction versus random insertional harm.
Marasmus is not biotech; keep comparisons inside this chapter: penicillin (fungus) versus streptomycin (Streptomyces); wine (grapes) versus beer (malt); yoghurt (thermophilus + bulgaricus) versus butter (Lactococcus path); biogas methane versus fossil LPG cost; insulin from rDNA versus extraction from animals historically.
Quick strip: biotech = industrial life processes; yeast ethanol + CO₂; autoclave; support/suspended; Lactobacillus curd; Fleming antibiotic discovery, Waksman name; broad/narrow; Jenner vaccine; three vaccine generations; methanogens CH₄ anaerobic; plasmid + restriction + ligase; clone library; insulin 1982; Ti Agrobacterium; microinjection; bioremediation; gene therapy somatic three modes; SCID ADA; germ-line off-limits.
Say each with one example aloud: wine yeast, penicillin mould, Ti cotton, goat tPA, mercury bacteria, ex-vivo SCID stem cells. You are exam-ready when fermentation steps, rDNA tools, transgenic methods and gene-therapy types come without notes on the NIOS Module 5 public paper for this biotechnology lesson.
Biotechnology unites kitchen microbes and molecular tools. Definition first: industrial application of organisms and biological processes for human benefit. Health applications include antibiotics, vaccines, gene therapy goals and DNA fingerprinting. Environment applications centre on bioremediation. Agriculture seeks resistant and nutritious crops and sterile pest strategies. Food and industry scale cheese, yoghurt, alcohol, additives and plant-based industrial chemicals.
Industrial workhorses are yeasts, moulds, bacteria and actinomycetes. Fermentation is sugar to alcohol and CO₂ with ATP energy yield; Saccharomyces cerevisiae dominates brewery and bakery. Process control means sterilisation by autoclave, correct strain, inoculation mode, and stable temperature and pH. Dairy relies on lactic bacteria lowering pH and curdling casein; commercial tables pair specific species with yoghurt and butter.
Antibiotics are microbial products that block pathogen metabolism. Know discoverer, term-coiner, spectrum types, resistance, and source table rows for penicillin, streptomycin, tetracycline and cephalosporin. Vaccines train immunity with attenuated, recombinant or synthetic antigens. Vitamins such as C, B₂ and B₁₂ illustrate fermentation nutrition products. Biogas turns dung into methane fuel and manure under strict anaerobiosis and near-neutral pH.
Genetic engineering rearranges DNA deliberately. Recombinant DNA technology needs culture, restriction enzymes, plasmids, ligase and hosts. Cut sticky ends, paste with ligase, amplify in bacteria, store clones. Proteins and enzymes from clones transformed medicine and industry. Transgenics carry foreign genes via Ti plants or microinjection and retroviruses in animals. Bioremediation cleans toxins with engineered metabolism.
Gene therapy corrects defective genes in patients. Map SCID, haemophilia, sickle cell and PKU to missing products. Prefer somatic ex-vivo, in-vivo and antisense routes; avoid human germ-line engineering. State limitations: non-heritable somatic fixes, insertional mutagenesis risk, safety rules, single-gene scope and cost.
Closed-book drill again: definition; five areas; microbe list; fermentation equation and steps; dairy microbes; antibiotic definition and table; vaccine generations; biogas rules; rDNA tools and ten-step story; protein table five items; transgenic plant and animal examples; gene therapy three somatic types and four limits. Completing this list covers Lesson 30 terminals for Module 5 Emerging Areas.
Sample process memory: grape sugars become wine ethanol in bioreactors after sterile yeast inoculation; milk lactose becomes lactic acid under Lactobacillus so curd sets and preserves; cow dung becomes methane when methanogens work without oxygen at pH near seven; a human insulin gene becomes a drug when pasted into a bacterial plasmid, cloned, and expressed at factory scale. Health, food and environment all ride the same idea: program or harness living systems. You are exam-ready when these process stories and the rDNA–transgenic–therapy triangle all come without notes on the Module 5 biotechnology examination paper this year for every serious board candidate.
Most exam-important points from this chapter:
Biotechnology = industrial use of life and bioprocesses. Pillars: medicine, environment, agriculture, food, industry. Microbes make foods, drugs, fuel and chemicals.
Yeast: sugar → ethanol + CO₂. Autoclave, inoculate (support/suspended), control conditions. Yoghurt/cheese: lactic bacteria lower pH and curdle casein.
Antibiotic stops pathogen metabolism (Fleming; Waksman). Broad vs narrow; resistance/allergy limits. Vaccines: attenuated, rDNA, synthetic generations.
Restriction scissors + ligase glue + plasmid vector + host = recombinant clones. Insulin 1982 model. Proteins, enzymes, vaccines and novel antibiotics scale up.
Foreign gene → transgenic (Ti plants; microinjection animals). Bioremediation cleans toxins. Gene therapy: somatic ex-vivo/in-vivo/antisense; germ-line not practised.
PE-only questions for this chapter only. 8 item(s). No overlap with other lessons. Tap Show answer after you try each question.
Q1. A broad-spectrum antibiotic, used against pathogenic bacteria, is
Why it clicks: Broad-spectrum hits many bacterial types.
Q2. Which of the following bacteria helps to set milk into yoghurt?
Why it clicks: Lactic acid bacteria set milk to curd/yoghurt.
Q3. The disease for which bio-engineered vaccine has already been developed is
Why it clicks: Recombinant hepatitis B vaccine is textbook example.
Q4. Biotechnology helps in synthesizing enzymes from cloned genes. Your friend wants to manufacture meat tenderisers. Which enzyme would you recommend to him?
Why it clicks: Bacteria as enzyme factories via recombinant DNA.
Q5. Which one of the following is not the step of microinjection process in biotechnology?
Why it clicks: Microinjection = DNA into animal egg pronucleus.
Q6. (a) Following is the representation of how a plasmid isolated from bac terium that causes galls in several plants is used to produce transgenic plants. (i) Name the bacterium that causes galls in plants. (ii) Name the plasmid used to transmit the desired genes
Why it clicks: Natural plant genetic engineer = Agrobacterium Ti plasmid.
Q7. (b) Given below is the picture of a normal mouse
Why it clicks: Transgene changes phenotype (size) vs control mouse.
Q8. Fermentation has a number of industrial applications, like A. In bakeries for preparing bread, cakes and biscuits. B. In breweries for preparing wine and other alcoholic drinks. C. In producing vinegar and in the tanning of leather. D. All the above. Which of the following cells is involved in cell-mediated immunity? (a) Leukaemia (b) T-cells (c) Mast cells (d) Thrombocytes
Why it clicks: Yeast/bacterial fermentation = industry workhorse.
Six problems spanning this chapter’s NIOS Biology (314) syllabus. Every question is built from the notes and formula sheet: solve with definitions and equations first, then read the formal textbook-style write-up, the easy explanation, and the topic in depth (key relations, meaning, exam tips). If the question says draw, a labelled pencil sketch is provided. Explanations open by default.
Define biotechnology in one NIOS-ready sentence.
Final answer: Living systems used for useful products/processes
Traditional (fermentation) and modern (genetic engineering) both count.
Key relations: Use of living organisms/enzymes/cells for products & services. State the definition or law first (NIOS style), use correct biological terms, and end with a clear boxed conclusion.
Using life’s tools—yeast, enzymes, DNA tricks—to make useful things.
Read the question once for the idea, once for the details. Write the definition or equation, then apply it. Check labels and units if any numbers appear.
Not only GM crops—curd, bread, antibiotics too.
Linked to chapter notes (L30). Remember: Use of living organisms/enzymes/cells for products & services. Most exam errors mix up similar terms, reverse cause and effect, or skip labelled diagrams.
Open with a one-line definition, then use: Use of living organisms/enzymes/cells for products & services. For diagram questions, label every part asked and keep lines neat.
What is a restriction enzyme? What is a plasmid vector used for?
Final answer: Cuts DNA at sites; plasmid carries gene into host
rDNA technology needs cutting, joining (ligase) and delivery tools.
Key relations: Restriction endonuclease cuts DNA; Plasmid vector carries insert into host. State the definition or law first (NIOS style), use correct biological terms, and end with a clear boxed conclusion.
Molecular scissors cut DNA; plasmid taxis ferry the gene into bacteria.
Read the question once for the idea, once for the details. Write the definition or equation, then apply it. Check labels and units if any numbers appear.
Ligase is the molecular glue.
Linked to chapter notes (L30). Remember: Restriction endonuclease cuts DNA; Plasmid vector carries insert into host. Most exam errors mix up similar terms, reverse cause and effect, or skip labelled diagrams.
Open with a one-line definition, then use: Restriction endonuclease cuts DNA; Plasmid vector carries insert into host. For diagram questions, label every part asked and keep lines neat.
What does PCR achieve and name the heat-stable enzyme commonly used?
Final answer: DNA amplification; Taq polymerase
PCR is foundational for diagnostics, forensics, research.
Key relations: Amplifies DNA in vitro; Denature–anneal–extend cycles. State the definition or law first (NIOS style), use correct biological terms, and end with a clear boxed conclusion.
PCR photocopies DNA using a heat-tough enzyme from hot-spring bacteria.
Read the question once for the idea, once for the details. Write the definition or equation, then apply it. Check labels and units if any numbers appear.
Needs primers and thermal cycling.
Linked to chapter notes (L30). Remember: Amplifies DNA in vitro; Denature–anneal–extend cycles. Most exam errors mix up similar terms, reverse cause and effect, or skip labelled diagrams.
Open with a one-line definition, then use: Amplifies DNA in vitro; Denature–anneal–extend cycles. For diagram questions, label every part asked and keep lines neat.
Give three application areas of biotechnology with one example each.
Final answer: Medicine, agriculture, environment (with examples)
Applications must be weighed with biosafety and ethics.
Key relations: Insulin recombinant; vaccines; GM crops; bioremediation. State the definition or law first (NIOS style), use correct biological terms, and end with a clear boxed conclusion.
Make medicines, better crops, clean pollution—with care.
Read the question once for the idea, once for the details. Write the definition or equation, then apply it. Check labels and units if any numbers appear.
Bt toxin from Bacillus thuringiensis protects some GM crops from insects.
Linked to chapter notes (L30). Remember: Insulin recombinant; vaccines; GM crops; bioremediation. Most exam errors mix up similar terms, reverse cause and effect, or skip labelled diagrams.
Open with a one-line definition, then use: Insulin recombinant; vaccines; GM crops; bioremediation. For diagram questions, label every part asked and keep lines neat.
What is a transgenic organism?
Final answer: Organism with introduced foreign gene
Transgenics differ from traditional hybrids (species limits).
Key relations: Transgenic: organism with foreign gene stably expressed. State the definition or law first (NIOS style), use correct biological terms, and end with a clear boxed conclusion.
A living thing that has a gene from elsewhere built into its DNA on purpose.
Read the question once for the idea, once for the details. Write the definition or equation, then apply it. Check labels and units if any numbers appear.
Ethical/regulatory oversight required.
Linked to chapter notes (L30). Remember: Transgenic: organism with foreign gene stably expressed. Most exam errors mix up similar terms, reverse cause and effect, or skip labelled diagrams.
Open with a one-line definition, then use: Transgenic: organism with foreign gene stably expressed. For diagram questions, label every part asked and keep lines neat.
What is totipotency? How is it used in tissue culture?
Final answer: Cell can make whole plant; used to clone plants in culture
Tissue culture needs sterile media with hormones (auxin/cytokinin balance).
Key relations: Totipotency; explant → callus → plantlets; Micropropagation. State the definition or law first (NIOS style), use correct biological terms, and end with a clear boxed conclusion.
Plant cells can regrow a full plant in a jar—farmers get many clones fast.
Read the question once for the idea, once for the details. Write the definition or equation, then apply it. Check labels and units if any numbers appear.
Virus-free plants via meristem culture—application.
Linked to chapter notes (L30). Remember: Totipotency; explant → callus → plantlets; Micropropagation. Most exam errors mix up similar terms, reverse cause and effect, or skip labelled diagrams.
Open with a one-line definition, then use: Totipotency; explant → callus → plantlets; Micropropagation. For diagram questions, label every part asked and keep lines neat.