A biologist analyzes DNA sequences in three different primates. She finds primates "A" and "B" have almost exactly the same DNA sequences. DNA sequences in primate "C" are significantly different from those of primate "A" and primate "B". This information allows the biologist to infer that

primates A and B are more closely related to each other than they are to primate C

Explanation:

The study and the comparison of DNA sequences of various species is used in decoding genomic information as well as determining closely related or distant related species.

Closely related species are known to have almost the same DNA sequences when studied. For example, chimpanzees are known to be most closely related to humans and this because, studies show that they share about 99% of their DNA with humans. So also, although monkey is a primate, its DNA sequences is significantly different from humans and chimpanzee, making it less closely related to either humans or chimpanzee compared to the relationship between human and chimpanzee.

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step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.