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.

Verified step by step guidance

1. Identify the relationship between amino acids and mRNA: Amino acids are the building blocks of proteins, and their sequence in a protein is determined by the sequence of nucleotide bases in mRNA through the process of translation.
2. Understand the genetic code's redundancy: The genetic code is degenerate, meaning that most amino acids are encoded by more than one codon (sequence of three nucleotides in mRNA). This allows for different mRNA sequences to code for the same amino acid.
3. Consider species-specific codon usage: Different organisms might preferentially use certain codons over others to code for the same amino acid, a phenomenon known as codon bias. This can lead to variations in mRNA sequences across species even when the amino acid sequences are identical.
4. Examine evolutionary conservation: The presence of identical amino acid sequences in different species suggests that these protein regions are evolutionarily conserved due to their importance in function. However, the underlying mRNA sequences might still differ due to the degeneracy of the genetic code.
5. Conclude the relationship: While the identical amino acid sequences in the transport proteins of zebrafish, puffer fish, mice, and humans suggest a conserved function, it does not necessarily mean that the mRNA sequences are identical across these species due to the redundancy of the genetic code and species-specific codon preferences.