Which genes regulate the expression of structural genes without coding for a protein themselves?

Which genes regulate the expression of structural genes without coding for a protein themselves?

• A. Structural genes
• B. Regulatory genes
• C. Genotype
• D. Phenotype

Answer: (B)

Regulation of gene expression is controlled by regulatory genes that produce factors—often regulatory proteins or RNAs—that influence whether and how much transcription happens for other genes, such as structural genes. These regulators bind to DNA or interact with the transcription machinery to turn genes on or off or modulate their level of expression. In this setup, the regulators themselves are not the structural products; their job is to control the expression of the structural genes that do code for the cell’s components. Structural genes, by contrast, code for the proteins that make up cellular structures. The genotype refers to the organism’s genetic makeup, while the phenotype is the observable traits resulting from gene expression. Those terms describe different concepts, not regulatory roles. So regulatory genes best fit the description.

Regulation of gene expression is controlled by regulatory genes that produce factors—often regulatory proteins or RNAs—that influence whether and how much transcription happens for other genes, such as structural genes. These regulators bind to DNA or interact with the transcription machinery to turn genes on or off or modulate their level of expression. In this setup, the regulators themselves are not the structural products; their job is to control the expression of the structural genes that do code for the cell’s components.

Structural genes, by contrast, code for the proteins that make up cellular structures. The genotype refers to the organism’s genetic makeup, while the phenotype is the observable traits resulting from gene expression. Those terms describe different concepts, not regulatory roles. So regulatory genes best fit the description.