Advertisements
Advertisements
Question
Name the genes responsible for making Bt cotton plants resistant to bollworm attack. How do such plants attain resistance against bollworm attacks? Explain.
Advertisements
Solution
- The Bt toxin is encoded by the cry gene. The cry I AC and Cry II Ab control cotton boll worms, while the cry I Ab controls corn borer. Bt gene produces Bt toxin. This toxin provides resistance to plants against lepidopteron, coleopteron and dipterans pests.
- An example is Bt cotton, in which the gene from the bacterium that encodes for the toxin is incorporated. The activated Bt toxin binds to the surface of the midgut epithelium of the insects and causes swelling and cell lysis, which eventually leads to the death of the insects.
- In the process of producing insect-resistant crops, specific Bt toxin genes are isolated from B.thuringiensis, and incorporated into the crops. Since these toxins are insect specific, they do not harm the crops or humans.
APPEARS IN
RELATED QUESTIONS
Give an example of the source of thermostable enzyme DNA polymerase.
Explain the mechanism of action of restriction endonucleases that makes them suitable for genetic engineering.
What is plasmid?
Lytic cycle involves bacteriophage and ____________.
EcoRl & Hind III are the examples of ______
Which molecules are called molecular scissors? Why are they called so?
A recombinant DNA molecule was created by ligating a gene to a plasmid vector. By mistake, an exonuclease was added to the tube containing the recombinant DNA. How does this affect the next step in the experiment i.e. bacterial transformation?
| Oil spill is a major environmental issue. It has been found that different strains of Pseudomonas bacteria have genes to break down the four major groups of hydrocarbons in oil. Trials are underway to use different biotechnological tools to incorporate these genes and create a genetically engineered strain of Pseudomonas - a ‘super-bug’, to break down the four major groups of hydrocarbons in oil. Such bacteria might be sprayed onto surfaces polluted with oil to clean thin films of oil. |
(a) List two advantages of using bacteria for such biotechnological studies?
(b) For amplification of the gene of interest PCR was carried out. The PCR was run with the help of polymerase which was functional only at a very low temperature. How will this impact the efficiency of the PCR? Justify.
(c) If such bacteria are sprayed on water bodies with oil spills, how will this have a positive or negative effect on the environment? Discuss.
Explain the mechanism of PCR.
Give a reason for the following:
The diagram given below represents vector pBr322 which was modified by a research scholar Dr. Rayon, but the vector was rejected by his guide.

