To use a genetic sequence as a molecular clock,the changes in nucleotides in the sequence must have accumulated at a steady pace over time.Drawing on what you know about codons and redundancy in the genetic code,which type of change would most likely be the type that is useful for a molecular clock?

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The genetic code is redundant, meaning that many different codons can code for the same amino acid. Therefore, changes in the first or second nucleotide pairs of a codon may not result in any change to the amino acid sequence. On the other hand, changes in the third nucleotide pair of a codon may still result in the same amino acid being coded for, but there is less redundancy at this position, meaning that changes are more likely to result in a different amino acid being coded for. These changes are more likely to accumulate at a steady pace over time and therefore are more useful for a molecular clock.

To Use a Genetic Sequence as a Molecular Clock,the Changes