Concept explainers
a.
To determine:
The portion of sgRNA that corresponds to crRNA and tracrRNA as per the figure given in the book.
Introduction:
A sgRNA (Single guide RNA) is made up of crRNA and tracrRNA (Trans activating RNA). In the CRISPR technique, both parts of the sgRNA are combined in one single molecule.
b.
To determine:
The reason due to which the fact that inside the bacterial genome, the CRISPR locus does not possess any PAM sites is crucial. Also, determine the way in which these PAM sites help in immunity of bacteria.
Introduction:
In the genome of the bacterium, the CRISPR locus does not contain PAM (Protospacer adjacent motif) sites. These are short DNA (Deoxyribose
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ND STONY BROOK UNIVERSITY LOOSELEAF GENETICS: FROM GENES TO GENOMES
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