Final answer:
A constitutive operon is one that is continuously transcribed and translated, providing constant intermediate levels of protein products without being regulated by environmental conditions or specific molecules.
Step-by-step explanation:
The question pertains to the regulation of gene expression in prokaryotic cells, particularly about operons. An operon that encodes genes which are continuously transcribed and translated to provide constant intermediate levels of protein products is classified as constitutive. Such operons are not regulated by environmental conditions or by the presence or absence of specific molecules, thus allowing for constant gene expression of essential proteins needed by the cell for routine functions.