THE MOLECULAR BASIS OF INHERITANCE
DNA MAKES RNA MAKES PROTEIN
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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prevents DNA synthesis
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attaches to ribosomes during translation
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destroys amino acids before protein synthesis occurs
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blocks movement of RNA polymerase
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Detailed explanation-1: -A repressor is an RNA or DNA binding protein that inhibits gene expression. It often binds to the associated promoter or silencer. This prevents the binding of DdRP (DNA dependent RNA polymerase) to the promoter. Thus, it inhibits the transcription of genes.
Detailed explanation-2: -Repressor binding blocks RNA polymerase from binding with the promoter, thereby leading to repression of operon gene expression.
Detailed explanation-3: -Repressor proteins typically function through binding and blocking critical DNA sequences in the gene, such as the promoter where mRNA transcription starts. In bacteria, repressor and activator of gene expression are distinct from each other.
Detailed explanation-4: -A DNA-binding repressor blocks the attachment of RNA polymerase to the promoter, thus preventing transcription of the genes into messenger RNA. An RNA-binding repressor binds to the mRNA and prevents translation of the mRNA into protein.
Detailed explanation-5: -The lac repressor protein binds to the operator and blocks RNA polymerase from binding to the promoter and transcribing the operon. The promoter is the binding site for RNA polymerase, the enzyme that performs transcription. The operator is a negative regulatory site bound by the lac repressor protein.