In order for the coi gene to be useful for distinguishing among the different salmon species, which three statements must be true?

The correct answer for this question is this one:
The COI gene must be variable enough that there are at least a few differences between each salmon species. 
The COI gene must be conserved enough that the sequences can be aligned for comparison. 
The COI gene must be conserved enough that the same PCR primers work for all the species being tested.

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Answer and Explanation

COI gene which is cytochrome oxidase which is mitochodrially encoded is a protein that in human is encoded by the MT-CO1 gene. It is the main sub unit  of the   cytochrome c oxidase complex.

In order for the CO1 gene to be useful for distinguishing among the different salmon species:

The COI gene must be conserved enough that the sequences can be aligned for comparison.The COI gene must be variable enough that there are at least a few differences between each salmon species. The COI gene must be conserved enough that the same PCR primers work for all the species being tested.

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