Advertisements
Advertisements
प्रश्न
Bt cotton is not ______.
पर्याय
A GM plant
Insect resistant
A bacterial gene expressing system
Resistant to all pesticides
उत्तर
Bt cotton is not resistant to all pesticides.
APPEARS IN
संबंधित प्रश्न
How has RNAi technique helped to prevent the infestation of roots in tobacco plants by a nematode Meloidegyne incognitia?
What is the major advantage of producing plants by micropropagation?
Answer the following question.
How is a continuous culture system maintained in bioreactors and why?
Cry-genes have been introduced in:
A protoxin is ______.
Silencing of a gene could be achieved through tee use ______.
Assertion (A): In Bt cotton, B. thuringiensis produces a toxic insecticidal crystalline protein which destroys bollworms.
Reason (R): B. thuringiensis produces this toxic protein in an inactive form, but when an insect ingests this inactive protein, it is converted into active form of toxin due to the alkaline pH of gut which solubilises the crystals, which is responsible for the death of bollworm.
Insects in the Lepidopteran group lay eggs on maize crops. The larvae on hatching feed on maize leaf and tender cob. In order to arrest the spread of three such Lepidopteran pests, Bt maize crops were introduced in an experimental field.
A study was carried out to see which of the three species of lepidopteran pests was most susceptible to Bt genes and its product.
The lepidopteran pests were allowed to feed on the same Bt-maize crops grown on 5 fields (A-E).
The graph below shows the leaf area damaged by these three pests after feeding on maize leaves for five days.
Key for lepidopteran insect pest species
 |
Species I |
 |
Species II |
 |
Species III |
Insect gut pH was recorded as 10, 8 and 6 respectively for Species I, II and III respectively.
(a) Evaluate the efficacy of the Bt crop on the feeding habits of the three species of stem borer and suggest which species is least susceptible to Bt toxin.
(b) Which species is most susceptible to Bt-maize, and explain why?
(c) Using the given information, suggest why a similar effect was not seen in the three insect species.
|
RNA interference (RNAi) holds great potential as a therapeutic agent for the treatment of human diseases and as biocontrol agents in controlling pests in the field agriculture. An experiment was carried to study the use of 'RNAi' for the potential treatment of disorders of cholesterol metabolism. Some people possess genetic mutations with elevated levels of ApoB gene which predisposes them to coronary artery diseases. Lowering the amount ApoB can reduce the number of lipoproteins and lower the blood cholesterol. Tracy Zimmerman and her colleagues used RNAi in 2006 to reduce the level of ApoB in non human primates Cynomolgus monkeys. One group of monkeys were given RNAi treatment (small interfering RNAs, SiRNAs) (doses 1 mg/kg, SiRNAs), second group of monkeys were given RNAi treatment (doses 2.5 mg/kg, SiRNAs) and third group of monkeys were injected with saline. |
The results of the study are depicted in the graph below:
- How does the treatment with 2.5 mg/kg bring an effect on cholesterol metabolism when compared from 24 hours and 144 hours?
- Write any two natural sources from where dsRNA molecule could be obtained for silencing the specific mRNA.
- How is RNAi used in controlling the infection on the roots of tobacco plants by the nematode Meloidogyne incognitia?
Name (i) a GM cereal crop having enhanced nutritional value, (ii) the nutrient it is rich in.
