Question 1

Q1: Which part of the plant is best suited for making virus-free plants and why?

Accepted Answer

The meristem (apical and axillary) is the best part of the plant for making virus-free plants. This is because the meristematic tissue is a region of actively dividing cells and has a high metabolic rate, which is believed to interfere with virus multiplication. Consequently, even if the rest of the...

Question 2

Q10: Can you suggest a method to remove oil (hydrocarbon) from seeds based on your understanding of rDNA technology and chemistry of oil?

Accepted Answer

Yes, a method based on recombinant DNA (rDNA) technology, specifically RNA interference (RNAi), can be used to create seeds with reduced or no oil content. Oil synthesis in seeds is a metabolic pathway controlled by specific enzymes, which are encoded by genes. The method would involve these steps:...

Question 3

Q11: Find out from internet what is golden rice.

Accepted Answer

Golden Rice is a variety of rice (Oryza sativa) that has been genetically engineered to biosynthesize beta-carotene, a precursor of Vitamin A, in the edible part of the grain. Normal rice does not produce beta-carotene, which is why its grains are white. The presence of beta-carotene gives Golden Ri...

Question 4

Q12: Does our blood have proteases and nucleases?

Accepted Answer

Yes, our blood does contain both proteases and nucleases, but their activity is tightly regulated to prevent damage to the body's own tissues and essential molecules.    Proteases: These are enzymes that digest proteins. The blood contains many proteases as part of critical systems like the blood cl...

Question 5

Q13: Consult internet and find out how to make orally active protein pharmaceutical. What is the major problem to be encountered?

Accepted Answer

Making a protein-based pharmaceutical (like insulin or growth hormone) orally active is a major challenge in drug development. Several strategies are being researched to achieve this: Methods to make protein pharmaceuticals orally active: 1.  Enteric Coating: Encapsulating the protein drug in a poly...

Question 6

Q2: What is the major advantage of producing plants by micropropagation?

Accepted Answer

The major advantage of producing plants by micropropagation (tissue culture) is the ability to produce a very large number of plants from a single parent plant in a very short duration. All the plants produced through this method are genetically identical to the original plant from which they were g...

Question 7

Q3: Find out what the various components of the medium used for propagation of an explant in vitro are?

Accepted Answer

The nutrient medium used for the in vitro propagation of an explant is a sterile, gel-based medium containing various components essential for plant growth. These components are: 1.  Carbon Source: A source of energy, typically sucrose. 2.  Inorganic Salts: Provides essential macronutrients (like ni...

Question 8

Q4: 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 imma...

Accepted Answer

The correct answer is (c) toxin is inactive. Explanation: The Bt toxin is produced by the bacterium Bacillus thuringiensis in an inactive form called a protoxin. This protoxin only becomes active under the specific alkaline pH conditions found in the midgut of certain insects. Since the internal env...

Question 9

Q5: What are transgenic bacteria? Illustrate using any one example.

Accepted Answer

Transgenic bacteria are bacteria whose genetic material has been altered by the introduction and expression of a foreign gene from another organism using recombinant DNA technology. These are a type of Genetically Modified Organism (GMO). Example: Production of Human Insulin A prominent example is t...

Question 10

Q6: Compare and contrast the advantages and disadvantages of production of genetically modified crops.

Accepted Answer

Advantages of Genetically Modified (GM) Crops: 1.  Pest Resistance: GM crops like Bt cotton produce their own insecticide, reducing the need for chemical pesticides and increasing crop yield. 2.  Enhanced Nutritional Value: Crops can be fortified with essential nutrients. For example, Golden Rice is...

Question 11

Q7: What are Cry proteins? Name an organism that produce it. How has man exploited this protein to his benefit?

Accepted Answer

Cry Proteins: Cry proteins are a class of toxic, insecticidal crystal proteins. They are produced in an inactive form (protoxin) and become active only in the alkaline gut of certain insects. Organism: The organism that produces Cry proteins is the soil bacterium Bacillus thuringiensis (Bt). Exploit...

Question 12

Q8: What is gene therapy? Illustrate using the example of adenosine deaminase (ADA) deficiency.

Accepted Answer

Gene Therapy: Gene therapy is a collection of methods aimed at correcting a genetic defect to treat a disease. It typically involves inserting a normal, functional gene into an individual's cells to compensate for a non-functional or missing gene. Illustration with Adenosine Deaminase (ADA) Deficien...

Question 13

Q9: Digrammatically represent the experimental steps in cloning and expressing an human gene (say the gene for growth hormone) into a bacterium like E. co...

Accepted Answer

While a diagram cannot be drawn here, the experimental steps for cloning and expressing the human growth hormone gene in E. coli are as follows. A diagram would visually represent this process: 1.  Isolation of Gene and Vector:        The human DNA is extracted from human cells, and the gene for gro...

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