You have identified a previously unknown human gene that appears to have a role in autism. it is similar enough in dna sequence to a known mouse gene that you believe that the two genes may be evolutionarily related. you determine and compare the dna sequences, the predicted mrna sequences, and the predicted amino acid sequences corresponding to the two genes. you would expect to find the greatest sequence similarity from comparisons of the two:
a. dna sequences (13.6%)
  b. mrna sequences (3.9%)
  c. amino acid sequences (51.5%)
  d. all three comparisons are likely to show the same degree of sequence similarity (31.0%)

Amino acid sequences

Explanation:

The proteins perform the vast majority of functions in the cells. If a gene between a human and a mouse is evolutionarily related, it means that the function they do in the cell is quite similar in both species. This is the reason why the amino acid sequence would be the most similar.

In addition, there might be certain mutations in the DNA and therefore in the RNA between this 2 sequences that encode to the same amino acid sequence. More specifically speaking, there are more than one codon that encode to the same aminoacid. Thus, 2 different DNA/RNA sequence can give the same aminoacid sequence.

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.