Question

question 9 of 10
which structures are part of an operon in a prokaryotic cell?
a. an enhancer, an operator, and noncoding genes
b. a promoter, an operator, and genes that code for proteins
c. a repressor, a promoter, and gene - specific enzymes
d. a promoter, an enhancer, and associated transcription factors

Explanation:

In prokaryotic cells, an operon consists of a promoter (where RNA polymerase binds), an operator (regulatory region), and genes that code for proteins (structural genes). Enhancers (A, D) are typically in eukaryotes. Repressors (C) are separate regulatory proteins, not part of the operon structure itself. Gene - specific enzymes and associated transcription factors (C, D) are not core components of a prokaryotic operon.

Answer:

B. A promoter, an operator, and genes that code for proteins