Assertion (A): The Indian government established the Genetic Engineering Approval Committee (GEAC) to regulate GM research. Reason (R): GEAC ensures the validity of GM research and assesses the safety of introducing GM-organisms into public services due to the potential for unpredictable ecological results from genetic modification.
Genetic modification of organisms raises ethical concerns and can have unpredictable results when released into the ecosystem. GEAC was set up specifically to address these concerns by regulating and validating the safety and validity of GM research and public use of GM organisms.
Question 442 of 494
📘 CLASS XII
Assertion (A): Transgenic animals are designed to serve as models for investigating new treatments for human diseases. Reason (R): These animals, such as those modeling cancer, cystic fibrosis, or Alzheimer's, are engineered to specifically display the genetic factors that contribute to the development of these human diseases.
Transgenic animals are created to mimic human disease conditions by manipulating their genes. They serve as models for understanding disease mechanisms and testing potential drug therapies before human trials.
Question 443 of 494
📘 CLASS XII
Assertion (A): Somatic hybridisation involves the fusion of isolated naked protoplasts from two different plant varieties. Reason (R): The resulting somatic hybrids are always highly desirable for commercial exploitation because they successfully integrate all beneficial traits from both parent species.
A is True: Somatic hybridisation is the fusion of protoplasts (cells without cell walls) from two plants, followed by in vitro growth to form a new hybrid plant. R is False: For example, the hybrid Pomato (potato + tomato) did not possess the desired combination of characteristics for commercial utilization, despite the technical success of the fusion.
Question 444 of 494
📘 CLASS XII
Assertion (A): Micro-propagation is a method that allows the quick production of thousands of plants. Reason (R): These plants are referred to as somaclones because they are derived from somatic cells and are genetically identical to the original parent plant.
Micro-propagation uses tissue culture to rapidly produce large numbers of plants from a small explant. Because they are produced asexually from a single source, they are genetically uniform copies (somaclones).
Question 445 of 494
📘 CLASS XII
Assertion (A): RNA interference (RNAi) is a cellular defense mechanism found in all eukaryotic organisms. Reason (R): RNAi functions by using a double-stranded RNA (dsRNA) molecule to bind to and prevent the translation of a specific, complementary target mRNA, thus silencing the gene.
RNAi is a natural defense mechanism in eukaryotes against mobile genetic elements or viral genomes. R correctly describes the mechanism: dsRNA complementary to the target mRNA triggers silencing by inhibiting translation.
Question 446 of 494
📘 CLASS XII
Assertion (A): Introducing the gene for ADA into cells at an early embryonic stage is the only permanent cure for adenosine deaminase (ADA) deficiency. Reason (R): Gene therapy involving periodic infusion of engineered lymphocytes is considered curative because the lymphocytes are immortal.
A is True: Introducing the gene at the early embryonic stage allows the cells to become a permanent part of the immune system, providing a permanent cure. R is False: The engineered lymphocytes are *not* immortal, which is precisely why periodic infusion is necessary, making it a non-permanent solution.
Question 447 of 494
📘 CLASS XII
Assertion (A): An American company received a patent in 1997 on Basmati rice, which was derived by crossing traditional Indian farmer varieties with semi-dwarf varieties. Reason (R): This patent only restricted the sale of the 'new' Basmati variety in the US market, leaving international markets open for traditional Indian Basmati varieties.
A is True: The US Patent and Trademark Office granted a patent for a variety derived from Indian Basmati, claiming it as a novelty. R is False: The patent extended to functional equivalents and allowed the company to sell the variety in the US and *abroad*, potentially restricting others selling traditional Basmati.
Question 448 of 494
📘 CLASS XII
Assertion (A): Upon activation, the Bt toxin protein binds to the surface of the midgut epithelial cells of the insect. Reason (R): This binding action leads to the formation of pores, causing osmotic cell lysis and subsequently the death of the insect.
Once the protoxin is activated by the alkaline pH of the insect gut, it attacks the midgut cells. The toxin binds specifically, creating channels or pores that disrupt the osmotic balance, leading to cell swelling and lysis, which results in the death of the pest.
Question 449 of 494
📘 CLASS XII
Assertion (A): The first transgenic cow, Rosie, produced milk that was nutritionally superior for human consumption compared to normal cow milk. Reason (R): Rosie’s milk contained 2.4 grams per litre of human alpha-lactalbumin, making it a more balanced product for human babies.
Rosie was the first transgenic cow (1997) designed to improve milk quality. The milk was enriched with the human protein alpha-lactalbumin, specifically increasing the nutritional balance to better suit the needs of human babies.
Question 450 of 494
📘 CLASS XII
Assertion (A): Genetic modification of crops has reduced the reliance of farmers on chemical pesticides. Reason (R): GM crops like Bt cotton are pest-resistant, resulting in lower application frequency of external insecticides.
One major advantage of GM plants is the creation of pest-resistant crops, which addresses environmental concerns and cost issues associated with agrochemicals. Since the crop produces its own bio-pesticide (like Bt toxin), the need for chemical insecticide spraying is significantly reduced.
