Figure 9-17 Shows the Nucleotide Sequence from a Protein-Coding Region

Multiple Choice

Figure 9-17 shows the nucleotide sequence from a protein-coding region of a gene in humans, chimpanzees, and gorillas and the protein sequence produced from this gene.The seventeen amino acids encoded by this DNA are numbered below.The two codons that are not conserved in all three species have been boxed.These two codons code for amino acids 3 and 15. Figure 9-17
Which of these statements is consistent with these sequence-comparison data?

A) The gorilla sequence is more similar to the chimp sequence than to the human sequence.
B) Since these sequences are so similar, this protein must also be found in invertebrates.
C) The chimp DNA sequence has likely diverged at the DNA coding for amino acid 15 from the sequence found in the last common ancestor of humans and chimps.
D) The last common ancestor of chimps and gorillas most likely used AAA to code for amino acid number 3.