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Question: Briefly describe the major steps and chemical reactions involved in RNA polymerase-directed transcription. Answer: The RNA polymerase-directed transcription process consists of three major steps: Initiation, Elongation, and Termination. In Initiation, RNA Polymerase binds to the DNA promoter, leading to the reaction: RNA Polymerase + DNA_promoter -> RNA Polymerase-DNA_complex. During Elongation, RNA Polymerase adds complementary RNA nucleotides to the DNA template, represented by the reaction: RNA Polymerase-DNA_complex + NTP -> RNA Polymerase-DNA_complex + RNA_n+1. Termination occurs when RNA Polymerase encounters a termination signal, resulting in the reaction: RNA Polymerase-DNA_complex + Termination_Signal -> RNA Polymerase + DNA + RNA_molecule. This process allows for the synthesis of RNA molecules from a DNA template, enabling gene expression and protein synthesis.