Class 9 Biology Chapter 10 Biotechnology and its Applications MCQ with Answers

The CBSE Class 9 Biology exam has shifted toward single-correct-answer multiple-choice questions (MCQs) and assertion-reason formats. Chapter 10 on Biotechnology and its Applications is no exception. The NCERT syllabus emphasizes conceptual clarity over rote learning—meaning MCQs are the perfect tool to test whether you truly understand GM crop technology, how transgenic animals are created, and the mechanism of gene therapy. Unlike descriptive answers, MCQs force you to eliminate wrong options, which strengthens critical thinking. The assertion-reason MCQ format (common in CBSE) particularly tests Chapter 10 concepts: for example, 'Assertion: Bt cotton is pest-resistant. Reason: The Bt gene produces Cry protein toxic to lepidopteran insects.' Mastering MCQs also builds exam confidence and reduces time wastage. Studies show students who practise 30+ MCQs on a chapter score 15–20% higher than those who only read the textbook. This quiz provides exactly that systematic practice.

**Q1.** Which of the following is an example of a genetically modified crop? (A) Wheat grown in traditional farms (B) Bt cotton with insecticidal properties (C) Rice cultivated using old breeding methods (D) Maize pollinated naturally **Answer:** (B) | **Reason:** Bt cotton contains the Cry gene from *Bacillus thuringiensis*, making it pest-resistant—a classic example of GM crop technology. **Q2.** What does 'GM' stand for in GM crops? (A) General Manufacturing (B) Genetic Modification (C) Growth Management (D) Global Market **Answer:** (B) | **Reason:** GM stands for Genetic Modification, a biotechnology process inserting foreign genes into crop DNA. **Q3.** Which animal is commonly used as a transgenic model in medical research? (A) Cow (B) Mouse (C) Horse (D) Sheep **Answer:** (B) | **Reason:** Laboratory mice are transgenic animals widely used to study human genetic diseases due to genetic similarity and ethical approval. **Q4.** Gene therapy aims to treat diseases by: (A) Replacing faulty genes with healthy ones (B) Removing all genes from cells (C) Adding more copies of mutated genes (D) Preventing cell division entirely **Answer:** (A) | **Reason:** Gene therapy corrects genetic disorders by introducing functional genes to replace defective ones causing disease. **Q5.** Bt in Bt cotton stands for: (A) Biotechnology toxin (B) *Bacillus thuringiensis* (C) Bacterial toxic compound (D) Biopesticide technology **Answer:** (B) | **Reason:** Bt is the bacterium *Bacillus thuringiensis*, whose Cry proteins are lethal to lepidopteran insect larvae. **Q6.** Which of the following is NOT an application of biotechnology? (A) Production of insulin (B) Creating drought-resistant crops (C) Natural photosynthesis without modification (D) Gene therapy for cystic fibrosis **Answer:** (C) | **Reason:** Unmodified natural photosynthesis is a biological process, not a biotechnology application requiring human genetic intervention. **Q7.** A transgenic animal is one that contains: (A) Genes from its own species only (B) Foreign DNA inserted into its genome (C) Multiple copies of its native genes (D) Mutated genes that arose spontaneously **Answer:** (B) | **Reason:** Transgenic organisms have DNA from external sources inserted artificially—defining characteristic of transgenesis. **Q8.** Genetically modified crops are designed to improve: (A) Only crop colour (B) Yield, nutrition, and pest/disease resistance (C) Soil texture (D) Water taste **Answer:** (B) | **Reason:** GM crops enhance yield potential, nutritional content (e.g. Golden Rice), and herbicide/pest resistance—core biotech goals. **Q9.** Which gene therapy approach is used to correct haemophilia? (A) Somatic gene therapy (B) Germ-line gene therapy (C) Surgical removal of blood cells (D) Antibiotic injection **Answer:** (A) | **Reason:** Somatic gene therapy targets body cells (not reproductive cells), making it ethical and reversible for blood-clotting disorders. **Q10.** The process of inserting a foreign gene into a plant cell is called: (A) Hybridization (B) Transfection (or genetic transformation) (C) Pollination (D) Fermentation **Answer:** (B) | **Reason:** Transfection/genetic transformation is the technical method of introducing foreign DNA into plant or animal cells.

**Q11.** Golden Rice is a genetically modified crop developed to address: (A) Protein deficiency (B) Vitamin A deficiency (C) Iron toxicity (D) Excess carbohydrate intake **Answer:** (B) | **Reason:** Golden Rice contains β-carotene (provitamin A), engineered to combat Vitamin A deficiency—a major public health initiative. **Q12.** A transgenic goat produces human insulin in its: (A) Blood serum (B) Milk (C) Saliva (D) Urine **Answer:** (B) | **Reason:** Pharming uses mammary glands of transgenic animals to produce therapeutic proteins like insulin in milk. **Q13.** Which of the following best explains why Bt crops reduce pesticide spraying? (A) They repel all insects (B) They produce Cry protein toxic to target pests (C) They have thicker leaves (D) They grow faster than pest reproduction **Answer:** (B) | **Reason:** Bt crops express Cry toxin lethal to lepidopteran larvae, reducing need for external chemical pesticides. **Q14.** Gene therapy for severe combined immunodeficiency (SCID) involves: (A) Removing immune cells permanently (B) Inserting functional ADA gene into patient's lymphocytes (C) Eliminating all white blood cells (D) Using antibiotics to kill pathogens **Answer:** (B) | **Reason:** SCID therapy corrects adenosine deaminase (ADA) deficiency by introducing the functional ADA gene into T lymphocytes ex vivo. **Q15.** A recombinant protein produced in bacteria is typically used for: (A) Building plant cell walls (B) Producing hormones like human growth hormone (HGH) (C) Creating photosynthetic pigments (D) Enhancing soil nutrients **Answer:** (B) | **Reason:** Recombinant bacteria (e.g. *E. coli*) are engineered to produce human proteins like insulin, HGH, and vaccines cost-effectively. **Q16.** The main ethical concern with germ-line gene therapy is that: (A) It is cheaper than somatic therapy (B) Genetic changes are heritable and affect future generations (C) It only works in plants (D) It requires no regulatory approval **Answer:** (B) | **Reason:** Germ-line modifications alter sperm/egg/embryo DNA, permanently changing the human gene pool—raising moral and societal concerns. **Q17.** Herbicide-resistant GM crops allow farmers to: (A) Stop using any chemicals (B) Spray herbicide to kill weeds without harming the crop (C) Grow crops without sunlight (D) Increase soil salinity **Answer:** (B) | **Reason:** Herbicide-resistant crops (e.g. Roundup Ready soy) tolerate glyphosate, enabling selective weed control. **Q18.** A transgenic chicken that lays eggs containing pharmaceutical proteins is an example of: (A) Cloning (B) Pharming (C) Selective breeding (D) Spontaneous mutation **Answer:** (B) | **Reason:** Pharming uses animals as bioreactors—genetically engineered to produce therapeutic proteins in eggs, milk, or blood. **Q19.** Which restriction enzyme would be used to cut DNA at specific sites during genetic engineering? (A) Lipase (B) Amylase (C) Restriction endonuclease (D) Protease **Answer:** (C) | **Reason:** Restriction endonucleases (e.g. EcoRI) recognize and cleave DNA at specific palindromic sequences—essential for cloning. **Q20.** The primary risk associated with releasing GM crops into the environment is: (A) Increased rainfall (B) Gene flow to wild relatives, potentially disrupting natural ecosystems (C) Reduction in oxygen levels (D) Enhanced photosynthesis in all plants **Answer:** (B) | **Reason:** Transgenes can transfer from GM crops to wild species, creating unintended ecological consequences—a major biosafety concern.

**Q21.** **Assertion (A):** Bt toxin is harmless to humans and other non-target organisms. **Reason (R):** Cry protein receptors are specific to lepidopteran insect larval midgut epithelial cells. (A) Both A and R are true; R correctly explains A (B) Both A and R are true; R does NOT explain A (C) A is true; R is false (D) A is false; R is true **Answer:** (A) | **Reason:** Cry toxin acts only in acidic insect guts with specific receptors; humans lack these, ensuring safety—R fully explains A. **Q22.** **Assertion:** Gene therapy using ex vivo approach is safer than in vivo therapy. **Reason:** Ex vivo therapy allows screening of modified cells before reintroduction into the patient. (A) Both A and R are true; R correctly explains A (B) Both A and R are true; R does NOT explain A (C) A is true; R is false (D) A is false; R is true **Answer:** (A) | **Reason:** Ex vivo (outside body) permits quality control and verification before cell transplantation, reducing complication risk. **Q23.** A GM crop carries a marker gene (e.g. antibiotic resistance) primarily to: (A) Help the crop fight bacterial infections (B) Identify transformed cells during genetic engineering (C) Improve crop flavour (D) Increase photosynthetic rate **Answer:** (B) | **Reason:** Selectable marker genes allow researchers to distinguish successfully transformed cells from non-transformed ones during cloning. **Q24.** In somatic gene therapy for haemophilia, the therapeutic gene is introduced into: (A) Bone marrow stem cells (B) Liver cells (C) Reproductive cells (D) Skin cells only **Answer:** (A) or (B) [most textbooks accept both] | **Reason:** Somatic therapy targets non-reproductive cells like bone marrow (source of blood cells) to restore clotting factor production. **Q25.** **Assertion:** Transgenic animals created for pharmaceutical production are more cost-effective than traditional fermentation methods. **Reason:** A single transgenic animal can produce large quantities of recombinant protein over its lifetime. (A) Both A and R are true; R correctly explains A (B) Both A and R are true; R does NOT explain A (C) A is true; R is false (D) A is false; R is true **Answer:** (A) | **Reason:** Pharming animals produce therapeutic proteins continuously (e.g. human insulin in goat milk), reducing production costs significantly. **Q26.** A disease-resistant GM crop incorporates a R gene (resistance gene) from a wild relative. Which statement is INCORRECT? (A) The R gene encodes a protein recognizing pathogen elicitors (B) The transgenic crop can resist all pathogens (C) R gene activation triggers plant immune response (D) Wild species sharing the R gene provided the genetic source **Answer:** (B) | **Reason:** R genes are pathogen-specific; a single R gene confers resistance to only one or few related pathogens, not all. **Q27.** In CRISPR-Cas9 gene editing, the sgRNA (single guide RNA) serves to: (A) Permanently block all DNA replication (B) Direct Cas9 enzyme to the precise target DNA sequence (C) Destroy the entire chromosome (D) Produce insulin in edited cells **Answer:** (B) | **Reason:** sgRNA acts as a molecular GPS, guiding Cas9 endonuclease to cut DNA at exact genomic locations. **Q28.** A transgenic mouse model for Alzheimer's disease carries the human APP gene (amyloid precursor protein). This approach allows researchers to: (A) Cure Alzheimer's in humans directly (B) Study amyloid-β plaque formation and test potential therapies in a living organism (C) Eliminate all neurodegenerative diseases (D) Replace human neurons **Answer:** (B) | **Reason:** Transgenic disease models mimic human pathology, enabling drug screening and mechanistic research before clinical trials. **Q29.** **Assertion:** Gene therapy is contraindicated (not recommended) for germ-line cells. **Reason:** Modifications to germ cells are irreversible and pass to all offspring, raising ethical and regulatory concerns. (A) Both A and R are true; R correctly explains A (B) Both A and R are true; R does NOT explain A (C) A is true; R is false (D) A is false; R is true **Answer:** (A) | **Reason:** Germ-line editing is prohibited in most countries because heritable changes affect future generations unpredictably. **Q30.** A biotechnology company develops a drought-tolerant GM maize by introducing an aquaporin gene (water channel protein). This genetic modification improves yield by: (A) Reducing water absorption completely (B) Enabling more efficient water uptake and retention in plants (C) Eliminating photosynthesis (D) Decreasing transpiration rate to zero **Answer:** (B) | **Reason:** Aquaporins facilitate water transport across cell membranes, helping crops survive water stress—a climate-resilience trait.

Examiners design plausible distractors to test depth of understanding. Here are frequent traps in Biotechnology MCQs: **Trap 1: Confusing GM Crops with Hybrid Crops** Hybrid crops result from crossing two different pure-breeding lines (traditional breeding); GM crops carry foreign genes inserted via molecular techniques. If a question asks 'How are Bt cotton and hybrid cotton different?'—hybrid is not genetically modified, but Bt cotton is. **Trap 2: Over-Generalizing Cry Toxin Safety** Cry proteins are safe for humans *at the concentrations in food*, but high laboratory doses may show toxicity in some studies. Never choose an option stating 'Bt toxin is 100% safe for all organisms'—accurate answer is 'safe for humans and non-target organisms in practical food quantities.' **Trap 3: Mixing Up Somatic and Germ-Line Therapy** Somatic therapy affects only the patient (non-heritable); germ-line therapy affects offspring (heritable). A trap might say 'Gene therapy for cystic fibrosis is germ-line' when it's actually somatic. Check whether the disease is in reproductive cells. **Trap 4: Assuming All Transgenic Animals Are Clones** Transgenic ≠ Clone. Transgenic animals carry inserted foreign genes; clones are genetic copies. A trap might say 'Dolly the sheep is transgenic' when Dolly was a clone (though clones with transgenes exist). **Trap 5: Equating Gene Therapy with Gene Editing** Gene therapy *adds or corrects* genes; gene editing (e.g. CRISPR) *modifies* existing genes. If asked 'What does gene therapy do?'—don't choose an option only describing editing. **Trap 6: Overstating Environmental Risk** While gene flow is a real concern, options stating 'GM crops will destroy all wild ecosystems' are hyperbolic. Accurate answers acknowledge risk but recognize regulatory oversight. Start a 3-day free trial at cbsetutor.ai to practise distinguishing realistic from exaggerated biotechnology claims.

Board exams demand speed without sacrificing accuracy. Here's a proven strategy for tackling Biotechnology MCQs: **Step 1: Pre-Exam Preparation (1 week before)** Spend 2–3 days memorizing core definitions: transgenic, pharming, somatic therapy, Bt toxin mechanism, and GM crop traits. Use flashcards. On day 4–5, solve all 30 MCQs in this quiz without time pressure to build conceptual confidence. Review errors immediately. **Step 2: Timed Practice (3–4 days before)** Solve 10–15 MCQs in 20 minutes (≈2 minutes per question). This trains your speed. Flag difficult assertion-reason questions but don't stall—return after easier questions. **Step 3: Exam-Day Tactics** **Easy MCQs (1–2 minutes each):** Read the question once, identify the correct answer using elimination, move on. Examples: 'What does GM stand for?', 'Name a transgenic animal.' **Medium MCQs (2–3 minutes each):** These require reasoning. Read question + all four options, eliminate obviously wrong ones (e.g. 'Photosynthesis enhancement' for a SCID gene therapy question is irrelevant), then choose the best remaining option. **Hard/Assertion-Reason MCQs (3–4 minutes each):** Read assertion first, then reason. Determine if both are true; if yes, check if reason *explains* assertion. Don't rush this section—it's worth the time investment. **Step 4: Flag and Review** If unsure after 90 seconds, mark with a dot (•) and return later. Finish all easy questions first, then medium, then hard. Last 5 minutes: review flagged questions only if time permits. **Step 5: Avoid Common Time-Wasters** Don't re-read questions obsessively. Don't change answers unless you have new information. Don't second-guess elimination choices. Trust your preparation. **Estimated Timing for Full Chapter 10 MCQ Section:** If exam has 30 MCQs on mixed chapters, allocate ~25–30 minutes. Chapter 10 might represent 8–10 questions; budget 15–20 minutes for these, leaving buffer time for other chapters.

Use this checklist to verify readiness: ✓ **GM Crops Knowledge:** - Can name 3 examples (Bt cotton, Golden Rice, herbicide-resistant soy) - Understand how Bt toxin kills insect larvae specifically - Know benefits (yield, nutrition, pest resistance) and risks (gene flow, biodiversity) ✓ **Transgenic Animals:** - Define transgenic: contains foreign genes from different species - Distinguish from cloning and selective breeding - Explain pharming: using animals to produce therapeutic proteins (insulin, vaccines) - Name model organisms: mouse, goat, chicken ✓ **Gene Therapy:** - Somatic therapy (body cells, non-heritable) vs. germ-line (reproductive cells, heritable) - Ex vivo (outside body) vs. in vivo (inside body) methods - Real examples: haemophilia, cystic fibrosis, SCID - Ethical concerns: germ-line prohibition, informed consent, long-term safety ✓ **Molecular Tools:** - Restriction enzymes cut DNA at specific sites - Plasmids carry foreign genes into cells - Selectable markers identify successfully transformed cells - CRISPR-Cas9: guide RNA directs enzyme to target sequence ✓ **Exam Readiness:** - Solved all 30 MCQs in this quiz with ≥80% accuracy - Reviewed errors and understood reasoning - Completed timed practice rounds - Memorized definitions and key examples - Familiar with assertion-reason logic If you've checked all boxes, you're ready for Chapter 10 questions on your board exam. For personalized doubt-clearing and adaptive practise on Biotechnology topics, explore cbsetutor.ai's AI-driven Class 9 Biology module.