Final answer:
During transcription, a gene is transcribed into a complementary strand of mRNA, which acts as a copy of the DNA code and carries genetic instructions for protein synthesis. Transcription is the first step in gene expression and follows the stages of initiation, elongation, and termination.
Step-by-step explanation:
During the process of transcription, a gene is transcribed into a complementary strand of mRNA. This mRNA molecule acts as a copy of the DNA code in the gene and carries the genetic instructions for protein synthesis. The flow of genetic information from DNA to RNA to protein is described by the central dogma of molecular biology. Transcription includes the stages of initiation, elongation, and termination, and it is the first step in gene expression.