15. The first transgenic plants expressing engineered foreign genes were tobacco plants produced by the use of
A.Agrobacterium tumefaciens
B.Bacillus thuringiensis
C.Arabidopsis thaliana
D.Streptomyces hygroscopicus

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16. Transgenic plants
A.contain foreign genes in their cells
B.are used to produce human antibodies
C.both (a) and (b)
D.are plants that differ in geographical locations

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17.  Low temperatures induce the expression of many cold-induced genes. Transgenic plants with improved cold tolerance have been produced by
A.expressing the protein that activates expression of these genes all the time in plants
B.cooling plants using the Peltier effect
C.expressing a gene for production of antifreeze (ethylene glycol) in plants
D.increasing evaporative cooling from leaf surfaces

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18. Nitrilase is encoded by
A.gene bxn in Klebsiella pneumoniae
B.bar gene in Streptomyces spp
C.both (a) and (b)
D.none of these

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19. If the goal were to create a plant resistant to an insecticide, which cell-based plant technology would be most effective?
A.Clonal propagation
B.Cybridization
C.Protoplast fusion
D.Mutant selection

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20. What are the various disadvantages of cross protection?
A.Possibility of mutations in inducing mild virus strain
B.Possibility of synergism between inducing virus and other unrelated virus
C.Possibility of unnecessary spread of mild virus
D.All of the above

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21. Which of the following gene is transferred to plants that detoxify the herbicide atrazine?
A.Nitrilase
B.Glutathione S-transferase (GST)
C.Phosphinothrium acetyl transferase
D.All of these

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