简答题\n In lac operon, an inducer binds to the _______ and inactivates it so that it no longer can bind to the ______. Transcription by RNA polymerase occurs. A、operator, repressor B、repressor, operator C、repressor, activator binding site D、activator binding site, operator\n简答题\n The activator binding site is __________ of the operon. A、near the promoter B、several hundred base pairs from the promoter C、near the promoter or several hundred base pairs from the promoter D、in the inner sites\n简答题\n ______ is commonly found in prokaryotic DNA-binding proteins. A、Zinc finger B、Leucine zipper C、Helix-turn-helix Structure D、All the above\n简答题\n The catabolite repression is a _____ control of transcription. A、positive B、negative C、positive and negative combind D、neither positive nor negative\n简答题\n Zinc finger and Leucine zipper are commonly found in Prokaryotic DNA-binding proteins. A、True B、False\n简答题\n In negative control, transcription of the operon occurs when the repressor is unable to bind to the ________. A、promotor B、operator C、SD sequence D、activator binding site\n简答题\n Most DNA-binding proteins interact with DNA in a sequence-specific manner. A、True B、False\n简答题\n Most DNA-binding proteins interact with DNA in minor groove of DNA. A、True B、False\n简答题\n _______ occurs when an external signal does not directly enter the cell but instead is detected by a sensor that transmits it to the rest of the regulatory machinery. A、Quorum sensing B、Sensory transduction C、Signal transduction D、Two-component regulation\n简答题\n The upstream RNA region, which acts as a riboswitch, binds _______ and results in translational blockage of the downstream protein-encoding sequence. A、antisense RNA B、peptides C、RNAi D、metabolites\n