Biotechnology and Its Applications Class 12 Notes - CBSE Biology Chapter 12

Chapter summary

Biotechnology and its Applications covers how engineered organisms and genes are turned into useful products across agriculture, medicine and industry, from Bt crops and RNAi pest resistance to recombinant insulin, gene therapy and transgenic animals. It also looks at the ethics, biopiracy and GEAC regulation behind GMOs. For NEET this is a high-yield, fact-dense chapter where direct one-mark questions on Bt toxin, golden rice, Humulin and ADA gene therapy are common.

Chapter notes
🃏 Flash Cards: Biotechnology and its Applications

Class 12 Biology · Chapter 10 – swipe through all 10 cards to understand the whole chapter.

🧬Start here1/10

What Biotechnology Delivers

Applied biotechnology turns living systems into useful products for agriculture, medicine and industry.

Best catalyst · Optimal conditions · Downstream processing

GMO = an organism whose genes have been altered by manipulation.

  • Every bioprocess needs the best catalyst (improved microbe/enzyme)
  • Plus optimal conditions (temperature, pH, substrate) for it to work
  • Plus downstream processing to purify the final product
🌾Big picture2/10

Three Application Fields & Food Routes

NCERT names three fields where biotech is applied, against the backdrop of how we grow more food.

Fields: healthcare · agriculture · environment/industry

Don’t confuse the 3 research problems with the 3 application fields.

  • Food routes: agrochemical, organic, genetically engineered farming
  • Green Revolution tripled food but needed costly agrochemicals
  • Biotech offers GMOs as a more sustainable alternative
🌽Core concept3/10

Genetically Modified Crops

GM crops are engineered to resist stress and pests and to improve nutrition.

Golden rice → vitamin-A (β-carotene) enriched

Also reduces pesticide use and post-harvest losses.

  • Tolerate abiotic stress: cold, drought, salt, heat
  • Reduce pesticide dependence and post-harvest losses
  • Raise mineral-use efficiency and nutritional value
🐛Most-tested4/10

Bt Toxin & the cry Gene

Bacillus thuringiensis makes an insecticidal protein whose gene is engineered into crops.

cry gene → Cry protein (Bt toxin); cryIAc + cryIIAb → Bt cotton

Gene is written cry (lowercase, italic); protein is Cry.

  • cryIAc, cryIIAb → cotton bollworms (lepidopterans)
  • cryIAb → corn borer
  • Bt cotton is the classic NEET example
⚗️Mechanism5/10

How Bt Toxin Kills the Insect

The toxin is stored harmlessly until an insect’s gut activates it.

inactive protoxin → alkaline gut activates → binds midgut → pores → lysis

Bacterium is safe because the toxin stays an inactive protoxin (crystal).

  • Insect eats inactive protoxin crystals
  • Alkaline pH of insect gut solubilises and activates the toxin
  • Active toxin binds midgut epithelium, forms pores, insect dies
🔇Key process6/10

RNA Interference (RNAi)

A cellular defence in eukaryotes that silences a specific mRNA using complementary dsRNA.

sense + antisense RNA → dsRNA → silences nematode mRNA

This is post-transcriptional gene silencing; needs a dsRNA trigger.

  • dsRNA binds the complementary mRNA and blocks translation
  • Used to make tobacco resistant to nematode Meloidogyne incognita
  • Genes delivered via Agrobacterium; parasite can’t survive
💉Medicine7/10

Recombinant Insulin (Humulin)

Human insulin was the first genetically engineered protein therapeutic.

Chain A (21 aa) + Chain B (30 aa) joined by disulphide bridges

Eli Lilly, 1983: A and B chains made separately in E. coli, then joined.

  • Body first makes pro-insulin with an extra C-peptide
  • C-peptide is removed during maturation
  • Recombinant route avoids allergy from animal-source insulin
🩺Medicine8/10

Gene Therapy & Molecular Diagnosis

Correcting a faulty gene, and detecting disease before symptoms appear.

First gene therapy (1990): ADA deficiency (SCID)

Lymphocyte ADA cDNA is temporary; permanent cure needs early embryonic bone-marrow cells.

  • Gene therapy inserts a normal gene to correct a defect
  • PCR amplifies tiny pathogen nucleic acid (HIV, cancer)
  • ELISA uses antigen-antibody interaction for early detection
🐄Core concept9/10

Transgenic Animals

Animals carrying a deliberately introduced foreign gene; over 95% are mice.

Rosie (1997) → human α-lactalbumin (2.4 g/L) in milk

Molecular pharming = making valuable proteins in animals.

  • Uses: study physiology, disease models, biological products
  • Also vaccine safety testing and chemical (toxicity) testing
  • First transgenic cow = Rosie; product = human alpha-lactalbumin
⚖️Ethics & law10/10

Biopiracy, Biopatents & GEAC

GMOs raise biosafety, ethical and ownership concerns that need regulation.

Biopiracy examples: Basmati · Turmeric (Haldi) · Neem

GEAC = Genetic Engineering Approval Committee (India).

  • GEAC approves GM research and safety of GMO release in India
  • Biopatent: a patent on a biological entity, product or process
  • Biopiracy: using bio-resources/knowledge without authorisation or payment
Swipe Click a card to focus 10 cards
📝 Practice Biotechnology and its Applications — 10 NEET PYQs
Real previous-year questions · with answers & solutions
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Tap an option to check your answer and see the worked solution. Every question is a real NEET previous-year question.
Q1NEET 2021
With regard to insulin, consider the statements: I. C-peptide is not present in mature insulin. II. The insulin produced by rDNA technology has C-peptide. III. The pro-insulin has C-peptide. IV. The A-peptide and B-peptide of insulin are interconnected by disulphide bridges. Choose the correct combination:
Correct answer: C. I is true (mature insulin lacks C-peptide), III is true (pro-insulin has the C-peptide), IV is true (A and B chains are linked by disulphide bridges). II is false – rDNA insulin is made by joining A and B chains and does NOT carry the C-peptide. Hence the true statements are I, III and IV.
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Q2NEET 2021
When gene targetting involving gene amplification is attempted in an individual’s tissue to treat a disease, it is known as:
Correct answer: B. Gene therapy is the correction of a genetic defect by introducing/targetting a functional gene into a patient’s tissue. Molecular diagnosis is about detecting disease, biopiracy is unauthorised use of bio-resources, and safety testing uses transgenic animals – none describe therapeutic gene targetting.
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Q3NEET 2020
Match the organism with its use in biotechnology and select the correct option: A. Bacillus thuringiensis 1. Cloning vector B. Thermus aquaticus 2. Construction of the first recombinant DNA molecule C. Agrobacterium tumefaciens 3. DNA polymerase (Taq) D. Salmonella typhimurium 4. Cry proteins
Correct answer: A. Bacillus thuringiensis is the source of Cry (Bt) proteins (A-4); Thermus aquaticus supplies the thermostable Taq DNA polymerase used in PCR (B-3); Agrobacterium tumefaciens is a natural cloning vector for plants (C-1); the first recombinant DNA molecule was made using a plasmid from Salmonella typhimurium (D-2). Hence A-4, B-3, C-1, D-2.
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Q4NEET 2020
Bt cotton variety, developed by the introduction of a toxin gene of Bacillus thuringiensis (Bt), is resistant to:
Correct answer: D. The Bt cry genes (cryIAc, cryIIAb) make a toxin that kills the cotton bollworm, an insect pest. So Bt cotton is resistant to insect pests, not fungi or nematodes (those need other strategies), and certainly not to predators.
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Q5NEET 2020
RNA interference is used for which of the following purposes in the field of biotechnology?
Correct answer: B. RNAi (post-transcriptional gene silencing) was used to make tobacco resistant to the nematode Meloidogyne incognita: host-produced sense + antisense RNA form dsRNA that silences a vital nematode mRNA, so the parasite cannot survive. The other options are achieved by different strategies, not RNAi.
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Q6NEET 2020
The laws and rules made to prevent the unauthorised exploitation of bio-resources are termed as:
Correct answer: B. Bioethics is the set of laws and rules framed to prevent unauthorised exploitation of bio-resources. Biopiracy is the unauthorised exploitation itself, biopatenting is the granting of patents on biological products/processes, and bioengineering applies engineering to biology.
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Q7NEET 2019
If an agricultural field is liberally irrigated for a prolonged period of time, it is likely to face the problem of:
Correct answer: D. Prolonged over-irrigation causes salts to accumulate in the topsoil (irrigation salinity) as water evaporates and leaves dissolved salts behind. Salinity is an abiotic stress that GM crops are engineered to tolerate. It is not primarily metal toxicity, alkalinity or acidity.
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Q8NEET 2016
Which part of the tobacco plant is infected by Meloidogyne incognita?
Correct answer: C. Meloidogyne incognita is a root-knot nematode that infects the roots of the tobacco plant, reducing yield. RNAi was used to protect the plant by silencing a vital nematode gene.
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Q9NEET 2011
The maximum number of existing transgenic animals belongs to which group?
Correct answer: B. Over 95% of all existing transgenic animals are mice, which are widely used as models for studying disease and gene function. Fish, cow and pig make up only a small fraction.
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Q10NEET 2010
Genetic engineering has been successfully used for producing:
Correct answer: A. Transgenic mice are used to test the safety of vaccines (e.g. the polio vaccine) before human use. Rosie’s milk was enriched in human alpha-lactalbumin (not high-fat ghee milk), so option C is wrong, and the other options are not established successful uses.
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Frequently Asked Questions

What is biotechnology and its applications about?

It is the applied side of biotechnology, where genetically engineered organisms and enzymes are used to make useful products for agriculture, medicine and industry. Major examples include Bt cotton, golden rice, recombinant insulin, gene therapy and transgenic animals.

How does the Bt toxin kill insects?

Bacillus thuringiensis makes the toxin as an inactive crystal protoxin, so the bacterium itself is safe. When an insect eats it, the alkaline pH of the insect gut solubilises and activates the toxin, which binds the midgut epithelium, creates pores and lyses the cells, killing the insect.

What is the difference between RNA interference and the Bt toxin strategy for pest resistance?

RNA interference silences a specific pest gene by using a complementary double-stranded RNA that blocks translation of that mRNA, as used against the nematode Meloidogyne incognita in tobacco. The Bt strategy instead inserts a cry gene so the plant makes a Cry protein toxin that physically destroys the insect gut, as in Bt cotton.

How is recombinant human insulin (Humulin) produced?

Mature human insulin has an A chain of 21 amino acids and a B chain of 30 amino acids joined by disulphide bridges. In 1983 Eli Lilly produced the two chains separately in E. coli using recombinant DNA technology and then joined them, avoiding the allergy risk of animal-derived insulin.

Is Biotechnology and its Applications important for NEET and what is its weightage?

Yes, it is part of the NEET Class 12 Biology syllabus and usually contributes about 1 to 2 questions per paper. It is scoring because most questions are direct fact recall on Bt toxin, golden rice, RNAi, Humulin, ADA deficiency gene therapy, Rosie the transgenic cow and GEAC.

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