Read the given passage and answer the following questions:
Biocontrol refers to the use of biological methods for controlling plant diseases and pests. In modern society, these problems have been tackled increasingly by the use of chemicals – by use of insecticides and pesticides. In agriculture, there is a method of controlling pests that relies on natural predation rather than introduced chemicals. The very familiar beetle with red and black markings – the Ladybird, and Dragonflies are useful to get rid of aphids and mosquitoes, respectively. An example of microbial biocontrol agents that can be introduced in order to control butterfly caterpillars is the bacteria Bacillus thuringiensis (often written as Bt ). Because of the development of methods of genetic engineering in the last decade or so, the scientists have introduced B. thuringiensis toxin genes into plants. Such plants are resistant to attack by insect pests. A biological control being developed for use in the treatment of plant disease is the fungus Trichoderma. Trichoderma species are free-living fungi that are very common in the root ecosystems. They are effective biocontrol agents of several plant pathogens. Baculoviruses are pathogens that attack insects and other arthropods. The majority of baculoviruses used as biological control agents are in the genus Nucleopolyhedrovirus. These viruses are excellent candidates for species-specific, narrow spectrum insecticidal applications. They have been shown to have no negative impacts on plants, mammals, birds, fish or even on non-target insects. This is especially desirable when beneficial insects are being conserved to aid in an overall integrated pest management (IPM) programme, or when an ecologically sensitive area is being treated.
Trichoderma is a biocontrol agent of plant pathogens. Its species Trichoderma polysporum produces a bioactive molecule used as an immunosuppressive agent in organ-transplant patients. This molecule is:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Cyclosporin A
Microbes make several bioactive molecules used in medicine. Trichoderma polysporum, the same genus that controls plant pathogens, produces cyclosporin A. Cyclosporin A suppresses the immune system, so it is given to organ-transplant patients to help prevent rejection of the new organ. By contrast, statins (from the yeast Monascus purpureus) lower blood cholesterol, and streptokinase (from Streptococcus) dissolves blood clots.
NCERT Extract:
Chemicals, Enzymes and other Bioactive Molecules – “… Streptokinase produced by the bacterium Streptococcus and modified by genetic engineering is used as a ‘clot buster’ for removing clots from the blood vessels of patients who have undergone myocardial infarction leading to heart attack. Another bioactive molecule, cyclosporin A, that is used as an immunosuppressive agent in organ-transplant patients, is produced by the fungus Trichoderma polysporum. Statins produced by the yeast Monascus purpureus have been commercialised as blood-cholesterol lowering agents.”