Question

multiple choice question

which kind of lac operon gene encodes an enzyme that is needed to catabolize lactose?

ribosomal
structural
regulatory

Explanation:

Identify the function of operon gene classes

The lac operon contains structural genes (lacZ, lacY, and lacA) that encode functional enzymes (such as \(\beta\)-galactosidase) directly involved in the catabolism and transport of lactose.

Differentiate from other gene classes

Regulatory genes (such as lacI) encode proteins that control transcription (like the repressor), rather than enzymes that catabolize the substrate. Ribosomal genes encode components of ribosomes, which are not part of the lac operon.

Determine the correct option

Genes encoding enzymes for lactose catabolism belong to the structural class of genes.

Answer:

• Ribosomal
• Structural (Correct answer)
• Regulatory