NCERT Solutions Class 12 Biology Chapter 10 Biotechnology and Its Applications

In Class 12 Biology Chapter 10, Biotechnology and Its Applications, students learn how modern biotechnology is used to solve real-world problems in health, agriculture, and the environment. This chapter explains the production of genetically modified crops, therapeutic proteins, vaccines, and diagnostic tools. It also introduces ethical and safety concerns related to the use of genetically modified organisms, helping students understand both the benefits and responsibilities that come with biotechnological advances.

ALLEN offers expertly curated NCERT Solutions to help students navigate these high-weightage topics that simplify into clear, structured explanations. Our seasoned biology faculties have designed these solutions, ensuring that technical processes like the maturation of pro-insulin or the silencing of mRNA are easy to grasp. These solutions are thoroughly aligned with the updated NCERT syllabus, providing the precise terminology and diagrammatic guidance needed to score maximum marks.

1.0Download NCERT Solutions Class 12 Biology Chapter 10 Biotechnology and Its Applications : Free PDF

This chapter explains how biotechnology is applied in medicine, farming, and environmental protection. The NCERT Solutions for Class 12 Biology Chapter 10 Biotechnology and Its Applications help students revise key uses and practise textbook questions easily. Download the free PDF now to study anytime and prepare confidently for exams.

2.0Key Concepts of Class 12 Biology Chapter 10 Biotechnology and Its Applications

The chapter focuses on understanding how biotechnology is used in practical and beneficial ways. Some of the key lessons covered in this chapter are given below:

• Transgenic Organisms: Understanding how genetically modified plants and animals are created and used.
• Biotechnology in Medicine: Learning about insulin production, vaccines, and gene therapy.
• Genetically Modified Crops: Studying Bt cotton and crops with improved yield and pest resistance.
• Molecular Diagnosis: Understanding tools like ELISA and PCR used to detect diseases.
• Ethical and Safety Issues: Learning about biosafety, patents, and social concerns related to biotechnology.
• Applications in Environment: Studying the role of biotechnology in waste management and pollution control.

3.0NCERT Class 12 Biology Chapter 10 Biotechnology and Its Applications : Detailed Solutions

1. Which part of the plant is best suited for making virus-free plants and why? 

Ans: The apical meristem (shoot tip) of the plant is best suited for making virus-free plants.

This is because viruses usually do not reach the rapidly dividing meristematic cells, so plants grown from this part are generally free from viral infection.

2. What is the major advantage of producing plants by micropropagation? 

Ans: Micropropagation is a tissue culture technique in which a large number of genetically identical plants (clones) are produced from a small piece of plant tissue (explant) under sterile laboratory conditions.

• The major advantage of micropropation is that it helps in the rapid production of a large number of genetically identical plants (clones) in a short time.
• Also, these plants are usually healthy and disease-free.

3. Find out what the various components of the medium used for propagation of an explant in vitro are? 

Ans: The medium used for propagation of an explant in vitro contains the following components:

• Nutrients (macro and micro elements)
• Sugar (sucrose) as a source of energy
• Vitamins
• Plant growth regulators (auxins and cytokinins)
• Agar to solidify the medium
• Sterile water

4. Crystals of Bt toxin produced by some bacteria do not kill the bacteria themselves because – (a) bacteria are resistant to the toxin

(b) toxin is immature; 

(c) toxin is inactive; 

(d) bacteria encloses toxin in a special sac

Ans: (c) toxin is inactive

5. What are transgenic bacteria? Illustrate using any one example.

Ans: Transgenic bacteria are bacteria that have been genetically modified by introducing a foreign gene into their DNA so that they can produce a useful product.

Example: A human insulin gene is inserted into Escherichia coli (E. coli) to make it transgenic. This transgenic bacteria produces the human insulin which is used in the treatment of diabetes.

6. Compare and contrast the advantages and disadvantages of production of genetically modified crops. 

Ans: Advantages:

• Increased crop yield: GM crops are designed in such a way that they grow better and resist pests. This helps farmers get higher production per unit area.
• Reduction in pesticide use: Pest-resistant crops like Bt crops reduce the need for spraying chemical pesticides, making farming more economical and eco-friendly.
• Improved quality and nutrition: Some GM crops are modified to have better nutritional value, improved taste, or longer shelf life.
• Tolerance to abiotic stresses: These crops are designed to tolerate harsh conditions such as drought, salinity, and extreme temperatures to help cultivation under difficult environments.

Disadvantages

• Environmental concerns: GM crops may affect non-target organisms and can lead to loss of biodiversity in natural ecosystems.
• Development of pest resistance: Over time, pests may become resistant to the toxins produced by GM crops, reducing their effectiveness.
• High cost of seeds: GM seeds are usually expensive, which can be a financial burden for small and marginal farmers.
• Health and ethical issues: There are concerns about the long-term effects of GM food on human health and ethical issues related to genetic modification.

7. What are Cry proteins? Name an organism that produce it. How has man exploited this protein to his benefit? 

Ans: Cry proteins are crystalline insecticidal proteins made by the bacterium Bacillus thuringiensis (Bt). These proteins become active inside the gut of insect pests and cause their death.

Human use and exploitation: Scientists have produced Bt crops like Bt cotton by transferring the gene for Cry protein into crop plants. These plants that are transgenic produce the toxin themselves and kill the insect pests. This reduces the need for chemical pesticides and increases the crop yield.

8. What is gene therapy? Illustrate using the example of adenosine deaminase (ADA) deficiency. 

Ans: The process of introducing a normal, functional gene into a person’s cells to replace a defective gene and treat a genetic disorder is called gene therapy.

Example: Adenosine Deaminase (ADA) deficiency
ADA deficiency is a genetic disease in which the body cannot produce the enzyme adenosine deaminase, leading to a weak immune system. 

• In gene therapy, lymphocytes (white blood cells) are taken from the patient and grown in the laboratory. 
• A normal ADA gene is inserted into these cells using a suitable vector. 
• The corrected cells are then returned to the patient’s body, where they start producing the ADA enzyme and help improve the immune response.

9. Digrammatically represent the experimental steps in cloning and expressing an human gene (say the gene for growth hormone) into a bacterium like E. coli ?

Ans:

10. Can you suggest a method to remove oil (hydrocarbon) from seeds based on your understanding of rDNA technology and chemistry of oil? 

Ans: We can remove oil (hydrocarbon) from seeds using rDNA technology by introducing a gene that produces an oil-degrading enzyme into microorganisms.

• These genetically modified bacteria can be allowed to act on crushed seeds. 
• The enzyme they produce breaks down the oil (hydrocarbons) into simpler, water-soluble substances.
• These are easily separated from the solid seed material by washing or filtration.

This method combines biotechnology (rDNA) and chemistry of oils to make oil removal more efficient and eco-friendly.

11. Find out from internet what is golden rice. 

Ans: Golden Rice is a genetically modified (transgenic) variety of rice (Oryza sativa) that has been engineered to biosynthesize beta-carotene, which is a precursor of Vitamin A. Beta-carotene is a yellow-orange pigment (the same one found in carrots) that gives the rice grains a distinctive golden yellow color, hence the name.

• It was developed to combat Vitamin A Deficiency (VAD), which is a major cause of night blindness and childhood mortality in developing countries where rice is a staple food.
• Nutritional Value: It is an example of Biofortification, the process of increasing the nutritional value of crops through genetic engineering.

12. Does our blood have proteases and nucleases?

Ans: Yes, our blood contains proteases and nucleases.

• Proteases help in processes like breaking down of protein and blood clotting.
• Nucleases help in breaking down nucleic acids from dead cells or invading micro organisms.

13. Consult internet and find out how to make orally active protein pharmaceutical. What is the major problem to be encountered?

Ans: To make a therapeutic protein active when taken by mouth, scientists encapsulate or protect the protein so that it is not destroyed in the digestive system. This can be done by:

• Encapsulation (Liposomes/Nanoparticles): The protein is wrapped in a "bubble" of lipids (liposomes) or biodegradable polymers. This shield protects the drug from stomach acid and enzymes.
• Enteric Coating: Tablets or capsules are coated with a material like cellulose acetate phthalate that does not dissolve in the acidic pH of the stomach but dissolves in the neutral/alkaline pH of the small intestine.
• Chemical Modification: Modifying the protein’s structure (e.g., attaching polyethylene glycol or PEGylation) can make it more stable and resistant to enzymes.
• Use of Enzyme Inhibitors: Co-administering the drug with substances that temporarily deactivate the digestive enzymes in the immediate vicinity of the drug increases its effectiveness.
• Penetration Enhancers: Adding chemicals that temporarily loosen the "tight junctions" between intestinal cells to allow large protein molecules to slip into the blood.

Some Major problems encountered are:

• Digestion by stomach enzymes: Proteases in the stomach and intestine break down the protein into amino acids, making it inactive.
• Acidic pH of the stomach: The low pH can denature the protein, changing its structure and destroying its function.
• Poor absorption: Large protein molecules cannot easily pass through the intestinal wall into the bloodstream.
• Short half-life in the body: Even if absorbed, proteins may be quickly degraded or removed from the blood.
• Loss of activity during storage and transport: Proteins are sensitive to temperature and moisture, which can reduce their effectiveness.

4.0Key Features and Benefits of Class 12 Biology Chapter 10 Biotechnology and Its Applications

• Case-based explanations help students understand how biotechnology concepts are applied in real medical and farming situations.
• Example-driven answers connect classroom theory with products like insulin, vaccines, and pest-resistant crops.
• Visual revision through flow-style summaries supports quick recall before board exams.
• Practice exercises strengthen confidence in answering application-based and reasoning questions.
• Concept clarity supports early preparation for NEET and future studies in life science fields.
• Simple, student-friendly language makes complex biotechnological ideas easier to understand and remember.