Engineering Life: Miracles in Biotechnology Class 9 Question Answer Advanced Science Chapter 10
Chapter-wise Class 9 Advanced Science Solutions and NCERT Class 9 Advanced Science Chapter 10 Engineering Life: Miracles in Biotechnology Question Answer are useful for focused study. Engineering Life: Miracles in Biotechnology Class 9 Questions and Answers Engineering Life: Miracles in Biotechnology Question Answer Class 9 Quick Check Question 1. What is biotechnology? Answer: Biotechnology is […]
Chapter-wiseClass 9 Advanced Science Solutionsand NCERT Class 9 Advanced Science Chapter 10 Engineering Life: Miracles in Biotechnology Question Answer are useful for focused study. Engineering Life: Miracles in Biotechnology Class 9 Questions and AnswersEngineering Life: Miracles in Biotechnology Question Answer Class 9Quick CheckQuestion 1. What is biotechnology?Answer:Biotechnology is the use of living organisms or their parts to develop useful products and processes. Question 2. Give two examples from your daily life demonstrating the use of biotechnology. Answer:Curd formation using bacteria and bread making using yeast. Question 3. Why are microorganisms important in biotechnology?Answer:Microorganisms are important in biotechnology because they help in producing useful substances such as enzymes, medicines and fermented products. Question 4. Traditional BiotechnologyModern BiotechnologyUses natural microbial processesUses ……………. . techniquesUsed since ……………. . timesDeveloped in ……………. . timesExample: Making curd, bread, wineExample: Production of ……………. . using bacteria. Has limited control over the ……………. . Provides greater control over ……………. . Does not involve gene transferInvolves ……………. . modificationAnswer:Traditional BiotechnologyModem BiotechnologyUses natural microbial processesUses molecular and genetic techniquesUsed since ancient timesDeveloped in modern timesExample: Making curd, bread, wineExample: Production of insulin using bacteriaHas limited control over the processesProvides greater control over organismsDoes not involve gene transferInvolves genetic modificationQuestion 5. Why is temperature control important in fermenters?Answer:Temperature control is important because microorganisms grow and function best at specific temperatures. Question 6. What happens if contamination occurs?Answer:Contamination introduces unwanted microorganisms that can spoil the product and reduce yield. Question 7. Explain sterilisation and its importance in microbial growth. Answer:Sterilisation is the process of removing all unwanted microorganisms, and it is important to ensure pure growth of desired microbes. Check Your UnderstandingQuestion 1. Define biotechnology. Explain how microorganisms act as ‘life’s engineers’ with two examples. Answer:Biotechnology is the use of living organisms, such as microbes, or their cellular components to produce substances that are beneficial to humans. Microorganisms act as life’s engineers because they can be used or modified to produce useful things for us. Here are two examplesInsulin Production:The human insulin gene is introduced into E. coli, enabling it to produce insulin used to treat diabetes. This method is reliable and widely used. Bt Cotton:A gene from Bacillus thuringiensis is inserted into cotton plants, allowing them to produce a natural insecticide and protect themselves from pests. Question 2. Differentiate between traditional biotechnology and modern biotechnology using suitable examples. Answer:Traditional BiotechnologyModern BiotechnologyUses natural microbial processes without changing genes. Uses scientific techniques to deliberately modify the genes of organisms. Practiced since ancient times. Developed in modern times. Limited control over organisms and outcomes. Greater control over organisms and outcomes. Does not involve gene transfer. Involves genetic modification or recombinant DNA technology. Example: Making curd, bread, wine, and beer using yeast or bacteria. Example: Producing human insulin using bacteria, developing disease-resistant Bt cotton. Question 3. Why are fermenters used instead of open containers for industrial production? Give two reasons. Answer:Fermenters are used instead of open containers for industrial production for the following reasons:Controlled conditions:Fermenters provide precise control over temperature, pH, oxygen supply, and nutrient levels, ensuring optimal growth of microorganisms and maximum product yield. Prevention of contamination:Fermenters are sterilised and closed systems, which prevent the entry of unwanted microorganisms and ensure the purity and quality of the product. Question 4. Explain the importance of maintaining sterility inside a fermenter. What problems may arise if sterility is not maintained?Answer:Sterility means maintaining a completely contamination-free environment inside the fermenter. It is essential because the nutrient-rich medium can support the growth of unwanted microorganisms along with the desired ones. If sterility is not maintained, the following problems may ariseContamination: Unwanted microorganisms may enter the fermenter and compete with the useful microbes for nutrients, reducing their growth. Product spoilage: Contaminating microbes may produce undesirable substances that affect the quality and purity of the final product. Financial loss: The entire batch may get spoiled and may need to be discarded, leading to loss of time, resources and money. Question 5. Study the diagram of a fermenter in the chapter and answer the questions. (A) Identify two parts responsible for maintaining microbial growth. (B) What is the function of the stirrer in a fermenter?(C) Why is oxygen supply important in some fermenter?Answer:(A) Two parts responsible for maintaining microbial growthCooling jacket: It controls temperature and prevents overheating, ensuring proper growth of microorganisms. pH sensor: It monitors and maintains the pH of the medium, providing a suitable environment for microbial activity. (B) Function of the Stirrer (Impeller): The stirrer mixes the broth uniformly so that all microbial cells receive equal amounts of nutrients and oxygen, ensuring proper and even growth. (C) Importance of oxygen supply: Oxygen is essential for aerobic microorganisms to carry out respiration and produce energy. A continuous oxygen supply supports their growth and helps in efficient production of the desired product. Question 6. Using the data below, answer the questions about microbial growth. Time (hours)024681012No. of Microorganisms20307014014514090(a) During which time period does rapid microbial growth occur?Answer:Rapid microbial growth occurs between 2 and 8 hours, where the population increases sharply from 30 to 145, indicating the log (exponential) phase. (b) Identify the stationary phase from the data. Answer:The stationary phase occurs between 6 and 10 hours, as the population remains nearly constant (140-145-140), showing a balance between cell growth and death. (c) Suggest one reason why the microbial population decreases after a certain time. Answer:After 10 hours, the population decreases due to depletion of nutrients and accumulation of toxic waste products, leading to the death of microorganisms. Question 7. Microbes are used in food production, medicine and environmental protection. Analyse how biotechnology improves human life using any three examples. Answer:Biotechnology improves human life in several fields such as food production, medicine, and environmental protection, as explained belowFood Production:Microorganisms such as Lactobacillus are used to prepare curd, yoghurt, and cheese, while yeast is used in baking and brewing. Biotechnology enables large-scale production under controlled conditions, ensuring safe, nutritious food with improved shelf life. Medicine:Bacteria like E. coli are genetically engineered to produce human insulin. This provides a safe, pure, and continuous supply of insulin, replacing animal-based sources and helping in the effective treatment of diabetes. Environmental Protection:Microorganisms such as Pseudomonas are used in bioremediation to break down pollutants like oil spills, heavy metals, and pesticides. This helps clean the environment naturally and restores ecosystems without harmful chemicals. Question 8. A scientist wants to produce insulin using bacteria. Explain how modern biotechnology makes this possible. Why has traditional biotechnology not achieved this?Answer:The production of insulin using modern biotechnology are as followsScientists identify and isolate the human insulin gene from DNA using restriction enzymes. The same enzymes are used to cut a bacterial plasmid to create matching ends. The human insulin gene is inserted into the plasmid using DNA ligase, forming recombinant DNA. This recombinant plasmid is introduced into a bacterium such as E. coli, which becomes capable of producing insulin. The modified bacteria are grown in fermenters, where they multiply and produce insulin, which is then collected and purified. Traditional biotechnology relies only on natural microbial processes and does not involve genetic modification. It lacks the tools to isolate, transfer, and insert genes. Since insulin production requires the transfer of the human insulin gene into bacteria, it is only possible through modern biotechnology. Question 9. Biotechnology has helped increase food production but some people have ethical concerns about GM crops. Evaluate both the advantages and concerns. Answer:Biotechnology has improved food production through Genetically Modified (GM) crops, but it also raises important ethical concerns. Advantages of GM crops are as followsCrops such as Bt cotton and Bt corn are resistant to insect pests, reducing the need for chemical pesticides and lowering environmental pollution. Biofortified crops like Golden Rice provide essential nutrients such as Vitamin A, helping to reduce malnutrition. GM crops can be developed for higher yield, drought tolerance, and disease resistance, improving food security. Ethical concerns about GM crops are as followsGene flow: Modified genes may spread to wild plants through cross-pollination, leading to the development of resistant weeds. Harm to non-target organisms: Toxins in GM crops may affect beneficial insects like bees and butterflies, disturbing ecosystems. Patent control and equity: Large companies own GM seeds, which may force farmers to buy expensive seeds every season, increasing economic burden. Conclusion: While GM crops offer significant benefits in increasing food production, their use should be carefully regulated to prevent environmental risks and ensure fairness for farmers. Question 10. Design a simple biotechnology product to solve an environmental problem in your community. Answer:I would design a bio-enzyme drain cleaner to solve the problem of drains and water bodies getting blocked by organic and plastic waste in urban areas. It would use bacteria producing lipase enzymes to break down fats and oils, and fungi such as Trichoderma producing cellulase enzymes to decompose plant-based waste like leaves, paper, and food residues. These agents convert complex organic waste into simpler, harmless substances. When added to clogged drains, it breaks down organic waste, prevents blockage, reduces pollution in water bodies, and maintains smooth wastewater flow. This product is eco-friendly, biodegradable, and non-toxic. It helps reduce flooding, improves sanitation and water quality, and provides a low-cost alternative to chemical drain cleaners. Question 11. Which of the following is an example of traditional biotechnology?(A) Production of insulin using bacteria(B) Preparation of curd from milk(C) Development of disease-resistant crops(D) Gene transfer between organismsAnswer:(B) Preparation of curd from milkQuestion 12. Which microorganism is commonly used in bread making?(A) Bacteria(B) Virus(C) Yeast(D) AlgaeAnswer:(C) YeastQuestion 13. Which condition is necessary for a fermenter to work properly?(A) Contamination(B) Controlled temperature(C) Open environment(D) Absence of nutrientsAnswer:(B) Controlled temperatureQuestion 14. Genetic engineering mainly involves(A) mixing different foods(B) transfer of genes between organisms(C) increasing natural microbial growth(D) removing microorganisms from foodAnswer:(B) transfer of genes between organismsQuestion 15. During which phase do microorganisms show maximum growth?(A) Lag phase(B) Log phase(C) Stationary phase(D) Death phaseAnswer:(B) Log phaseQuestion 16. Assertion (A): Sterility must be maintained inside a fermenter. Reason (R): Contamination by unwanted microorganisms can reduce product quality. (A) Both A and R are true and R is the correct explanation of A. (B) Both A and R are true, but R is not the correct explanation of A. (C) A is true, but R is false. (D) A is false, but R is true. Answer:(A) Both A and R are true and R is the correct explanation of A. Question 17. Assertion (A): Modern biotechnology allows production of insulin using bacteria. Reason (R): Modern biotechnology involves genetic modification techniques. (A) Both A and R are true and R is the correct explanation of A. (B) Both A and R are true, but R is not the correct explanation of A. (C) A is true, but R is false. (D) A is false, but R is true. Answer:(A) Both A and R are true and R is the correct explanation of A. Engineering Life: Miracles in Biotechnology Class 9 MCQQuestion 1. A scientist uses restriction enzymes to cut a human gene and a bacterial plasmid. After mixing them together, no recombinant plasmid is formed. Which enzyme is most likely missing?(A) Restriction enzyme(B) Amylase(C) DNA ligase(D) ProteaseAnswer:(C) DNA ligaseDNA ligase joins the sticky ends of the cut gene and plasmid together. Without it, no recombinant plasmid can form even if cutting was successful. Question 2. Bt toxin is lethal to cotton bollworms but harmless to humans. What is the most accurate scientific reason?(A) Bt toxin is destroyed by high human body temperature(B) Bt toxin only activates in the alkaline gut of certain insect larvae, not in the human stomach. (C) Humans produce antibodies that neutralise Bt toxin immediately(D) Bt toxin only affects organisms with green pigment in their cellsAnswer:(B) Bt toxin only activates in the alkaline gut of certain insect larvae, not in the human stomach. Bt toxin activates specifically in the alkaline insect gut and binds to receptors absent in humans. The acidic human stomach simply denatures it harmlessly. Question 3. A microbiologist observes that new cells produced in a fermenter exactly equal cells dying, with nutrients depleting and waste accumulating. Which phase is this?(A) Log phase(B) Lag phase(C) Decline phase(D) Stationary phaseAnswer:(D) Stationary phaseThe stationary phase is where birth rate equals death rate exactly. In the Decline phase, population actually crashes rather than remaining stable. Question 4. A student claims traditional and modern biotechnology are essentially the same since both use microorganisms. Which statement best disproves this?(A) Traditional biotechnology uses only bacteria while modern uses only fungi(B) Modern biotechnology involves deliberate genetic manipulation while traditional relies entirely on natural microbial processes without gene transfer(C) Traditional biotechnology is practiced only at home while modern is only in laboratories(D) Modern biotechnology uses only synthetic chemicals, not microorganismsAnswer:(B) Modern biotechnology involves deliberate genetic manipulation while traditional relies entirely on natural microbial processes without gene transferThe key distinction is deliberate genetic modification in modern biotechnology versus natural microbial activity in traditional biotechnology. Options (a), (c) and (d) are factually incorrect. Question 5. A nutritionist argues eating carrots solves Vitamin A deficiency better than Golden Rice. What is the strongest scientific reason Golden Rice remains significant?(A) Golden Rice tastes better than carrots(B) Golden Rice grows faster than carrots in all climates(C) In regions where rice is the primary staple and carrots are inaccessible, Golden Rice delivers beta-carotene directly through the existing dietary staple(D) Carrots do not contain beta-carotene so they cannot address Vitamin A deficiencyAnswer:(C) In regions where rice is the primary staple and carrots are inaccessible, Golden Rice delivers beta-carotene directly through the existing dietary stapleGolden Rice addresses malnutrition within existing food habits of rice-dependent populations with limited dietary diversity. Option (d) is completely false as carrots are rich in beta-carotene. Engineering Life: Miracles in Biotechnology Class 9 MCQCase/Source Based QuestionsDirections (Q. Nos. 1 – 3): Read the following passage carefully and answer the questions that follow. Rajesh is a cotton farmer in Maharashtra who suffered devastating losses due to cotton bollworms. He previously used large quantities of chemical pesticides which damaged his soil. An agricultural officer introduced him to Bt cotton, developed by inserting a gene from a bacterium into cotton plant DNA. This gene causes the plant to produce Bt toxin in its leaves and stems. When a bollworm larva feeds on the plant, the toxin enters its gut and kills it within 1-2 days. The toxin is harmless to humans and beneficial insects. After planting Bt cotton, Rajesh dramatically reduced pesticide use, saving money and restoring soil health. Question 1. Name the bacterium from which the Bt toxin gene is derived. Answer:The Bt toxin gene is derived from Bacillus thuringiensis, a naturally occurring soil bacterium that produces proteins toxic to specific insect larvae. Question 2. How does Bt toxin kill bollworms without harming humans?Answer:Bt toxin activates in the alkaline gut of bollworm larvae and binds to specific gut receptors, causing gut wall breakdown and death. Human stomachs are acidic and lack these receptors, so the toxin is harmlessly denatured. Question 3. What technique was used to develop Bt cotton and what type of biotechnology does it represent?Answer:Recombinant DNA technology was used, involving the isolation and insertion of the Bt gene into cotton plant DNA. This represents modern biotechnology, specifically genetic engineering creating a transgenic plant variety. Very Short Answer Type QuestionsQuestion 1. A fermenter is sterilised before use but the product obtained is still contaminated. Suggest one possible reason for this. Answer:Sterilisation of the fermenter alone is insufficient if the nutrient culture medium, equipment, or inoculum itself was not properly sterilised beforehand. Contaminant microorganisms introduced through unsterilised medium can still thrive and spoil the desired product entirely. Question 2. Both Pseudomonas bacteria and Bacillus thuringiensis are used in biotechnology but for completely different purposes. Differentiate between their specific roles. Answer:Pseudomonas bacteria are used in bioremediation to break down harmful pollutants like hydrocarbons from industrial waste, protecting the environment. Bacillus thuringiensis provides the Bt toxin gene inserted into crops like cotton to create natural pest resistance without chemical pesticides. Short Answer Type QuestionsQuestion 1. Bio-enzymes are increasingly replacing harsh chemical cleaners in households. Explain why bio-enzymes are considered superior and name any two types used in cleaning products. Answer:Bio-enzymes are natural proteins derived from microbes like bacteria and fungi that break down tough stains including grease, fats and proteins effectively at low temperatures, saving energy and reducing harsh chemical exposure. They are skin-safe and eco-friendly. Two types used are proteases, which break down protein-based stains, and lipases, which dissolve fat and grease deposits efficiently. Question 2. A student argues that open containers can replace fermenters for producing antibiotics industrially since microbes grow in both. Construct a scientific argument against this claim. Answer:Open containers cannot maintain the sterile, controlled conditions essential for industrial production. Fermenters precisely regulate temperature through cooling jackets, oxygen supply through spargers, pH through automated sensors, and nutrient mixing through stirrers. Without these controls, contamination by unwanted microorganisms would destroy the culture, reduce product quality drastically and make large-scale consistent antibiotic production completely impossible. Question 3. Explain why the sparger and cooling jacket are both equally critical components in a fermenter, even though they perform completely opposite functions. Answer:The sparger pumps oxygen into the fermenter to support aerobic respiration, enabling microbes to grow and produce desired products efficiently. The cooling jacket removes excess heat generated by rapidly multiplying microbes, preventing them from dying due to overheating. Both maintain opposite but complementary conditions simultaneously, and failure of either component would collapse the entire microbial growth process irreversibly. Long Answer Type QuestionsQuestion 1. “Biotechnology has revolutionized agriculture, but it has also introduced serious ecological and ethical risks. ” Justify this statement by discussing both the agricultural benefits and the concerns associated with GM crops. Answer:Biotechnology has dramatically transformed agriculture through genetic engineering. Bt cotton and Bt corn were developed by inserting Bacillus thuringiensis toxin genes into crop DNA, creating plants that naturally kill bollworms and other larvae without chemical pesticides, reducing farmer costs and soil damage significantly. Golden Rice was engineered using maize and bacterial genes to produce beta-carotene, addressing Vitamin A deficiency that causes childhood blindness in rice-dependent populations. However, serious ecological risks exist including gene flow, where modified genes transfer through cross-pollination to wild plants creating uncontrollable super-weeds. Evolutionary pressure can cause pests to develop resistance to Bt toxin over generations, producing super-bugs harder to eliminate than original pests. Ethically, patent control by corporations forces poor farmers to repurchase expensive seeds annually rather than saving them, widening inequality between wealthy nations and developing countries significantly. Question 2. Blue, Green and Red biotechnology represent three distinct branches serving very different human needs. Explain each branch with a specific example and evaluate which branch you consider most critical for humanity’s future survival, justifying your answer scientifically. Answer:Blue biotechnology applies biotechnology to marine and freshwater organisms, increasing seafood supply, regulating waterborne diseases and developing new pharmaceutical drugs derived from marine life. Green biotechnology focuses on improving nutritional quality, quantity and eco-friendly production in agriculture, developing transgenic plants like Golden Rice and Bt cotton for better productivity, disease resistance and reduced pesticide dependency. Red biotechnology is medical biotechnology applied to manufacture life-saving pharmaceutical products including insulin produced through recombinant DNA technology, antibiotics, enzymes and vaccines benefiting millions globally. Red biotechnology is arguably most critical because diseases like diabetes affect hundreds of millions worldwide and pharmaceutical biotechnology directly produces life-sustaining medicines unavailable through any other method. Without insulin produced through genetically engineered bacteria, diabetic patients globally would face fatal consequences. This make Red biotechnology essential for immediate human survival compared to agricultural or marine applications despite their significant long-term importance.