Genetic Engineering And Biotechnology

The question revolves around the mechanism by which the insecticidal protein from a Bt (Bacillus thuringiensis) plant becomes lethal to insects. Bt plants produce a certain protein that is initially inactive. The transformation of this protein into its active form occurs under specific conditions.

Explanation: Bt toxin is a crystalline protein (Cry protein), which is inactive in its natural state. Upon ingestion by an insect, the alkaline conditions in the insect's gut convert this inactive form into an active toxin.

Process:

• Ingestion: The insect consumes parts of the Bt plant, taking in the Cry protein.
• Activation Conditions: The insect's gut is alkaline in nature. This condition is crucial because only in such an environment can the Bt protein become active.
• Protein Activation: The alkaline pH facilitates the unfolding of the Cry protein, changing its conformation to a form that can interact with the gut lining.
• Insect Mortality: The active form of the toxin binds to specific receptors in the insect gut lining, creating pores and eventually leading to cell lysis and insect death.

Conclusion: The correct answer is Alkaline pH of the gut, as this condition is essential for converting the inactive Cry protein into its active, insecticidal form.

In the context of Biology, the acronym "GEAC" stands for the "Genetic Engineering Approval Committee". This is a critical committee responsible for the assessment and authorization of activities related to genetic engineering in organisms. Below is the breakdown of the options provided:

• Genetic and Environmental Advisory Committee: This option incorrectly combines aspects of genetics and environmental considerations, which are not the primary focus of GEAC.
• Gene Establishment Approval Committee: This option misrepresents the scope by focusing on "gene establishment," which is not a recognized term in the context of GEAC.
• Genetic Engineering Advisory Committee: Although related, an advisory committee would only provide suggestions and not approvals, which is a key function of GEAC.
• Genetic Engineering Approval Committee: Correct. This option accurately represents GEAC's role in authorizing genetic engineering projects.

To solve the problem of matching List-I with List-II, we need to understand the role of each transgene:

• α-1-antitrypsin is a protein used in the treatment of diseases like emphysema, which is referenced by "Treat emphysema" (III).
• cryIAc is a gene from Bacillus thuringiensis used in genetically modified crops to control pests, specifically known for effectiveness against the Corn borer (II).
• Antisense RNA is a strategy used in genetic engineering to create resistance against pests such as Meloidgyne incognitia, a type of root knot nematode (I).
• cryIAb is another Bacillus thuringiensis gene, effective against Cotton bollworms (IV).

Now we can match each transgene in List-I with its correct application in List-II.

Thus, the correct answer is: (A) - (III), (B) - (II), (C) - (I), (D) - (IV).