THE MOLECULAR BASIS OF INHERITANCE
CLONING GENES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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in humans
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in bacteria
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in algae
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they are not natural-all restriction enzymes are made in the lab
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Detailed explanation-1: -Restriction enzymes are found in bacteria (and other prokaryotes). They recognize and bind to specific sequences of DNA, called restriction sites. Each restriction enzyme recognizes just one or a few restriction sites.
Detailed explanation-2: -Where do restriction enzymes come from? Restriction enzymes are found in bacteria. Bacteria use restriction enzymes to kill viruses – the enzymes attack the viral DNA and break it into useless fragments.
Detailed explanation-3: -4.18 Restriction Enzymes Restriction enzymes of bacteria catalyze the cleavage of a foreign DNA such as those injected by a phage (a virus that infects bacteria). Bacteria acquired those enzymes in order to defend themselves against such invasions. Each restriction enzyme cuts DNA at a specific recognition sequence.
Detailed explanation-4: -Restriction enzymes, or more formally ‘restriction endonucleases’ (REase), occur naturally in all free-living bacteria and archaea and serve to protect these microbes from infections by viruses and parasitic DNA molecules.
Detailed explanation-5: -In 1970, Hamilton O. Smith, Thomas Kelly and Kent Wilcox isolated and characterized the first type II restriction enzyme, HindII, from the bacterium Haemophilus influenzae.