Question

Place the steps in order below using the terms first, second, third, and so on.

Some viral DNA is incorporated into the bacterium's genome as a spacer.


Bacteria is exposed to phage (virus) for the first time and survives.


Cas-9 removes the targeted sequence of cutting it out of the bacterial genome.


The RNA acts as a guide for the protein


Cas-9 finds an exact DNA sequence match

in an invading virus.


Transcription occurs and RNA is made

from DNA.

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