Question

Researchers compared the amino acid sequences of the transport protein in zebrafish, puffer fish, mice, and humans. They found many stretches with identical sequences in all four species. Does this mean that the corresponding mRNA base sequences are also the same in these four species? Explain why or why not.

A) No because the redundancy of the genetic code means that it is possible for deferent codons to specify the same amino acids

B) Yes, because the amino acid sequences synthesized on base of mRNA sequence base is a result of translation, so if amino acid sequences are identical, the mRNA base sequences will be identical too.

C) Yes, because ail codons specify the same amino acids in all organisms.

D) No, because stretches with identical sequences in this species mean that the corresponding rRNA base sequences are also the same.

Answer 1

A) No because the redundancy of the genetic code means that it is possible for deferent codons to specify the same amino acids

Step-by-step explanation:

Redundancy in the genetic code makes that differences in the messenger RNA (mRNA) to be translated into the same amino acids, thereby differences in the mRNA might encode for the same protein sequence

Answer 2

A) No because the redundancy of the genetic code means that it is possible for different codons to specify the same amino acids

Step-by-step explanation:

There are 20 amino acids in nature whereas, there are 64 possible codons from 4 bases (adenine, guanine, uracil, and cytosine). Consequently, an amino acid can be coded for by more than one genetic codes. This is why the genetic codes are said to be redundant/degenerate.

Hence, having similar stretches of amino acid by the same organism does not corresponds to similar mRNA base sequence. For example, the codons UCC, UCU, UCA, and UCG all codes for the same amino acid serine.

The correct option is A.