Assertion (A): Thousands of plants produced through micro-propagation are genetically identical to the original parent plant. Reason (R): Micro-propagation is a tissue culture method where plants are regenerated from an explant, and the resulting offspring are referred to as somaclones.
Micro-propagation is mass production of plants via tissue culture. Since they are derived asexually from an explant, they are genetically identical (somaclones).
Question 412 of 494
📘 CLASS XII
Assertion (A): In mammals, insulin is initially synthesized as a pro-hormone. Reason (R): The pro-hormone contains an extra stretch called the C peptide, which is required for the proper folding of the molecule but is removed during maturation to form functional insulin.
The insulin pro-hormone must be processed to become mature and functional, involving the removal of the C peptide, which links chains A and B.
Question 413 of 494
📘 CLASS XII
Assertion (A): The choice of a specific Bt toxin gene for incorporation into a crop plant depends on the targeted pest. Reason (R): Most Bt toxins are insect-group specific; for instance, the protein encoded by cryIAb controls corn borer, while cryIAc controls cotton bollworms.
Bt toxin genes exhibit specificity. Different Cry proteins target different groups of insects (lepidopterans, coleopterans, dipterans).
Question 414 of 494
📘 CLASS XII
Assertion (A): Even if a plant is infected with a virus, it is possible to obtain virus-free plants by culturing the meristem. Reason (R): The apical and axillary meristems are typically free of viruses.
Virus particles often fail to reach the rapidly dividing cells of the meristem (apical and axillary), allowing scientists to culture this region in vitro to achieve virus-free plants.
Question 415 of 494
📘 CLASS XII
Assertion (A): PCR is commonly used in molecular diagnosis to detect pathogens before the appearance of disease symptoms. Reason (R): PCR can detect the presence of a pathogen by amplifying its nucleic acid even when the concentration of the bacteria or virus is very low in the body.
PCR’s high sensitivity allows for the amplification of trace amounts of pathogen DNA/RNA, enabling early diagnosis before the pathogen load is high enough to cause visible symptoms.
Question 416 of 494
📘 CLASS XII
Assertion (A): Recombinant therapeutics are safe and do not typically induce unwanted immunological responses in humans. Reason (R): Recombinant therapeutic drugs are genetically engineered to be structurally identical to natural human proteins.
Recombinant products are free from the risk of infection and, being identical to human proteins, are less likely to trigger adverse immune reactions than products sourced from non-human animals.
Question 417 of 494
📘 CLASS XII
Assertion (A): The milk produced by the first transgenic cow, Rosie, was nutritionally superior to natural cow-milk for human babies. Reason (R): Rosie produced milk enriched with human alpha-lactalbumin, making it a more balanced product.
Rosie produced human protein-enriched milk (2.4 grams per litre) containing the human alpha-lactalbumin, improving its nutritional balance for infants.
Question 418 of 494
📘 CLASS XII
Assertion (A): Somatic hybridisation involving the fusion of tomato and potato protoplasts successfully resulted in the formation of 'Pomato'. Reason (R): Pomato became a commercially successful hybrid plant because it displayed the complete set of desired characteristics from both parent species.
The formation of Pomato was achieved (A is True). However, R is False because the plant did not possess all the desired characteristics for commercial utilization.
Question 419 of 494
📘 CLASS XII
Assertion (A): Biopiracy is primarily a concern for developed industrialised nations because they are rich in traditional knowledge. Reason (R): Biopiracy refers to the unauthorized use of bio-resources and associated traditional knowledge, primarily of developing and underdeveloped nations, by multinational companies without compensatory payment.
A is False: Industrialized nations are rich financially but generally poor in biodiversity and traditional knowledge. R is True: This is the definition of biopiracy and highlights the exploitation of resource-rich developing nations.
Question 420 of 494
📘 CLASS XII
Assertion (A): Golden Rice is a genetically modified crop that is highly beneficial in preventing Xerophthalmia in developing countries. Reason (R): Golden rice has been enhanced for nutritional value as it contains an increased amount of Vitamin A.
Genetic modification has enhanced the nutritional value of food, exemplified by Golden Rice. Golden Rice is enriched with Vitamin A, which helps combat Vitamin A deficiency, a major cause of preventable blindness like Xerophthalmia.
