Biotechnology Principles and Processes: NCERT Solutions for Class 12

Biotechnology is a crucial topic in Class 12, combining natural and engineering sciences. Since Chapter 10: Biotechnology and Its Applications presents complex concepts, students often struggle. To help you succeed, we provide Biotechnology Principles and Processes NCERT Solutions that simplify these challenging topics.

At SimplyAcad, our comprehensive NCERT solutions for Chapter 10: Biotechnology and Its Applications are available for free. These solutions offer clear explanations and insights, making it easier for students to grasp the material. If you’re preparing for your 12th board exams, our resources will undoubtedly boost your confidence. Scroll down to access our detailed Biotechnology Principles and Processes NCERT Solutions and strengthen your understanding.

Understanding Biotechnology Principles: NCERT Solutions for Class 12

Question 1: Crystals of Bt toxin produced by some bacteria do not kill the bacteria themselves because:

(a) bacteria are resistant to the toxin.

(b) the toxin is immature.

(c) the toxin is inactive.

(d) bacteria enclose toxins in a special sac.

Solution:

(c) The toxin is inactive.

Bt toxin in bacteria exists in an inactive form called protoxin. When insects ingest this toxin, it becomes active, leading to the insect’s death.

Transgenic Bacteria and Biotechnology Applications: NCERT Solutions

Question 2: What are transgenic bacteria? Illustrate using any one example.

Solution:

Transgenic bacteria contain a foreign gene deliberately inserted into their genome. Scientists manipulate these bacteria to express the desired gene, producing valuable products. For example, E. coli bacteria can be genetically modified to produce human insulin. After the insulin gene is inserted into the bacteria’s plasmid, it enables the bacteria to produce insulin chains. Eventually, these chains are extracted and combined to form human insulin.

Advantages and Disadvantages of Genetically Modified Crops in Biotechnology

Question 3: Compare and contrast the advantages and disadvantages of genetically modified (GM) crops.

Solution:

Advantages:

• GM crops can withstand various abiotic stresses like cold, drought, and heat.
• They produce alternative resources, such as fuels, starches, and pharmaceuticals.
• Pest-resistant GM crops reduce reliance on chemical pesticides and increase productivity.
• Enhanced nutritional quality, such as golden rice, which is rich in Vitamin A.
• Reduced post-harvest losses and improved soil fertility due to better mineral usage.

Disadvantages:

• Unwanted genetic combinations may arise.
• There’s a potential risk of creating super weeds.
• GM crops might face reduced fertility.
• Health concerns, such as allergens and antibiotic resistance markers, may arise.
• GM crops can impact native biodiversity through genetic pollution.

Cry Proteins in Biotechnology Principles and Processes

Question 4: What are Cry proteins? Name an organism that produces them and explain their benefits.

Solution:

Cry proteins are toxins produced by the bacterium Bacillus thuringiensis. These proteins remain inactive in their natural state but become active in the alkaline pH of an insect’s gut, leading to the insect’s death. Cry proteins have been harnessed to create insect-resistant transgenic crops, such as Bt corn and Bt cotton.

Gene Therapy in Biotechnology Processes: NCERT Solutions

Question 5: What is gene therapy? Illustrate using the example of adenosine deaminase (ADA) deficiency.

Solution:

Gene therapy involves correcting malfunctioning genes by inserting or repairing them. For example, ADA deficiency, a genetic disorder caused by a missing adenosine deaminase gene, can be treated by inserting the functional gene into bone marrow cells. This treatment restores normal immune system function.

Cloning and Expression in Biotechnology: Understanding NCERT Solutions

Question 6: Diagrammatically represent the experimental steps in cloning and expressing a human gene (e.g., growth hormone) in E. coli.

Solution:

DNA cloning involves using a vector to insert a foreign DNA fragment into a host cell. For cloning the growth hormone gene into E. coli:

1. Isolate the DNA containing the growth hormone gene.
2. Insert this DNA into a plasmid vector.
3. Transform the plasmid into E. coli cells.
4. Grow the E. coli, which then produces the growth hormone protein.

rDNA Technology in Seed Oil Removal: NCERT Solutions for Biotechnology

Question 7: Suggest a method to remove oil (hydrocarbon) from seeds using rDNA technology.

Solution:

Recombinant DNA technology can identify and remove genes responsible for oil production in seeds. After using restriction endonucleases to cut these genes, treat the DNA with ligases to seal the broken ends. Cultivating the modified cells can produce plants with seeds low in oil content.

What is Golden Rice? Biotechnology Applications Explained

Question 8: What is golden rice?

Solution:

Golden rice is a genetically modified variety of rice enriched with Vitamin A. It contains beta-carotene, a precursor of Vitamin A, inserted into the rice through genetic engineering. This rice helps address Vitamin A deficiencies, especially in regions where this vitamin is scarce.

Understanding Proteases and Nucleases in Blood: NCERT Solutions

Question 9: Does our blood contain proteases and nucleases?

Solution:

No, blood does not contain active proteases or nucleases. While some proteases exist in inactive forms, they are not active in blood.

Creating Orally Active Protein Pharmaceuticals in Biotechnology

Question 10: How are orally active protein pharmaceuticals made, and what are the major challenges?

Solution:

Orally active protein pharmaceuticals, often vaccines, are produced by inserting antigen genes into plants, such as potatoes. However, a significant challenge is that proteases in the digestive system can degrade these proteins. To protect them, the proteins are encapsulated in coatings that dissolve only in the intestines.