Which of the following does not consist of a sequence of bases?

a: repressor





b: structural gene





c:promoter





d:regulator gene





e:operator

Which of the following does not consist of a sequence of bases?
The answer to your question is repressor, all the other are in fact DNA sequences. The repressor is a protein that binds to DNA adjacent and downstream to the promoter sequence. The binding of the protein block the pathway for RNA polymerase and prevents transcription of the gene. Therefore the repressor negatively regulates gene expression.
Reply:I am going to go with repressor, all the rest are part of the DNA strand. A repressor is a protein that binds to the operator and hence made up of amino acids and not nitrogenous bases.
Reply:a repressor

gladiolus