One way that a cell can turn off or prevent gene expression

How can small interfering RNAS (SİRNAS) and micro RNAS (miRNAs) regulate gene expression? Prevent transcription by binding to DNA and inhibiting transcription factors. Prevent transcription by inducing methylation. Prevent translation by binding to mRNA and degrading the MRNA strand. Prevent translation by binding to MRNA and blocking the ribosome.

True or false and explain why

True or false: Some bacterial genes are regulated by transcriptional activators rather than by repressors

Which of the following is not a mechanism of enzyme regulation? Activation by proteolysis O Multiple forms of enzymes Transfigural control Reversible covalent modification Allostery

A mutation that results in a premature (early) stop codon, will terminate transcription resulting in a shorter mRNA. True False

The nucleolus manufactures RNA. Tues or False

Eukaryotic regulation of gene expression occurs at the level of _____ transcription splicing and processing mRNA degradation translation all of the above

Which of the following is a method through which cells can control their gene expression?     Increase a gene's stability using post-translational modifications     Epigenetic modifications of the DNA or histones to regulate DNA avilability     phosphorylation of thymidines     formation of crosslinks between the DNA strands and the histones

Which DNA regulatory sequence speeds up transcription? a promoter b repressor c silencer d enhancer