Final answer:
In eukaryotes, the first product of a protein-encoding gene is messenger RNA (mRNA). Transcription creates mRNA from the DNA template, and translation uses the mRNA to produce a protein sequence.
Step-by-step explanation:
In eukaryotes, the first product of a protein-encoding gene is a messenger RNA (mRNA).
During the process of transcription, RNA polymerase II assembles at a gene promoter and creates a complementary mRNA strand from the DNA template. This mRNA is used as a template during translation, where the genetic code, represented by a sequence of three-nucleotide codons, is read and translated into a protein sequence consisting of amino acids.
The mRNA serves as an intermediate between the DNA sequence and the final protein product, allowing for the transfer and expression of genetic information.