Final answer:
An operon is a group of genes regulated together, found in prokaryotic cells, that includes a promoter, operator, and genes for related functions. It enables coordinated gene expression by allowing all genes within the operon to be expressed or repressed as a unit. Regulatory proteins that bind to the operator sequence control the operon's transcription.
Step-by-step explanation:
The term operon refers to a group of genes regulated together in the context of prokaryotic gene expression. An operon includes a promoter, operator, and one or more genes that encode for proteins related to a specific function. Regulation of gene expression in prokaryotic cells, particularly in bacteria such as E. coli, is often achieved through systems such as the Lac operon for lactose metabolism or the trp operon for tryptophan synthesis. Each operon is transcribed into a single mRNA molecule, facilitating coordinated regulation of genes, ensuring that all are expressed or none are expressed according to the cell's needs. Regulatory proteins, which can function as activators, repressors, or inducers, interact with the operator to control transcription.