Which of the following genetic elements is transcribed into a single mrna? 1)the inducer 2) the promoter 3) the repressor 4) the structural genes 5) the operator

The genetic element which is transcribed into a single mRNA is THE STRUCTURAL GENES.

The lac operon is found in organisms such as E coli. The lactose (lac) operon is made up of genes, which brings about metabolism of lactose in E coli. The operon is expressed only when glucose is absent and lactose is available. The lac repressor and CAP (Catabolite Activator Protein) are the two regulators, which turn the lac operon on and off.  

Structurally, the lac operon is made up of three different genes, which are Lac Z, Lac Y and Lac A. These three genes are transcribed as a single messenger RNA (mRNA) under the control of a single promoter. These genes function by specifying proteins, which make the E coli cells to make use of lactose for energy. In addition to the three genes, the lac operon also contains regulatory DNA sequences such as the promoter region, operator region and the CAP binding site.  

answer; the correct answer is desert plants;

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.