Which of the following statements best describes bacteria?

a. Introns are removed from the transcript before translation begins.

b. Genes that play a role in the same metabolic pathway are organized into an operator

c. The expressions of genes that play a role in the same metabolic pathyway is orchestrated by upstream enhancers.

d. Genes that play a role in the same metabolic pathway are organized into an operon.

d. Genes that play a role in the same metabolic pathway are organized into an operon.

Explanation:

In prokaryotic organisms like bacteria, polycistronic mRNAs exist which means that each gene does not have a separate promoter of its own. In fact many genes are under the control of a single promoter. These genes being a part of same metabolic pathway are organized into an operon. For example, lac operon and tryptophan operon. In lac operon, three genes named as β-galactosidase, permease and transacetylase are expressed under a single promoter which is known as lac promoter.

In contrast to this, in eukaryotes the mRNAs are monocistronic i. e. only a single gene is controlled under a single promoter.