Final answer:
Splicing does not occur in bacteria.
Step-by-step explanation:
The level of gene regulation that does not occur in bacteria is splicing. Splicing is a process in eukaryotes where introns are removed from the pre-mRNA, and the exons are joined together to form a mature mRNA molecule. In bacteria, the process of transcription, which involves the synthesis of mRNA from DNA, is not followed by splicing.