Insulin is a hormone produced by some pancreatic cells. Scientists have isolated the DNA sequence that codes for human insulin p
roduction Which of the following best predicts the effect of inserting this gene into the DNA of a bacterial cell? А) The recombinant bacterium will produce human insulin using its own transcription and translation machinery.
B) The recombinant bacterium will not transcribe the human insulin gene because this gene is not normally found in the bacterial genome.
C) The recombinant bacterium will transcribe the gene but will be unable to translate the mRNA.
D) The recombinant bacterium will die because it has been exposed to foreign DNA.
А) The recombinant bacterium will produce human insulin using its own transcription and translation machinery.
Explanation:
Recombinant DNA technologies refer to molecular biology techniques used to create chimeric DNA sequences by using genetic recombination techniques. The resultant recombinant DNA can further be used for the production of desired gene products (proteins) both in vitro and in living organisms. DNA recombinant techniques involve the insertion of desired DNA regions into an appropriate vector such as, for example, in a plasmid that is amplified in bacteria. For this purpose, the desired DNA fragment is inserted into a plasmid vector by digesting both the target DNA and plasmid insertion sites with an appropriate restriction enzyme. Subsequently, a DNA ligase is used to join both DNA fragments from their ends. Finally, the transformed bacterial (host) cells are selected to express the desired inserted gene.
The green colour of the unripe fruit is due largely to the presence of chlorophylls, and the development of different colours during ripening is due to the disappearance of these pigments and the synthesis of carotenoids.
