BIOTECHNOLOGY
APPLICATIONS OF BIOTECHNOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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To prevent being infected by viruses
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To help DNA get into the cell
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To be able to grow in an incubator
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They don’t-viruses have restriction enzymes
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Detailed explanation-1: -A bacterium uses a restriction enzyme to defend against bacterial viruses called bacteriophages, or phages. When a phage infects a bacterium, it inserts its DNA into the bacterial cell so that it might be replicated. The restriction enzyme prevents replication of the phage DNA by cutting it into many pieces.
Detailed explanation-2: -These enzymes occur naturally in bacteria as a defense against bacteriophages – viruses that infect bacteria. Bacterial restriction enzymes cut the invading bacteriophage DNA while leaving the bacterial genomic DNA unharmed due to addition of methyl groups.
Detailed explanation-3: -In vivo, these enzymes are involved in recognizing and cutting up foreign DNA entering the cell; their most likely role is thus protecting the bacteria against phage infection.
Detailed explanation-4: -Restriction enzymes provide a protective mechanism to the bacterial cell by cutting the foriegn DNA but the bacterial DNA is also prone to the action of these enzymes. Cutting its own DNA is prevented because some of the nucleotides of recognition sites have caps of methyl groups.
Detailed explanation-5: -Bacteria make enzymes that lock onto certain, short sequences of DNA and slice them apart. When a virus injects its genes, these so-called restriction enzymes shred them into genetic confetti, so that they can’t take over the cell.