Final answer:
The false statement about miRNA is that (c) miRNAs are produced from rRNAs. MiRNAs are transcribed from genomic DNA, not rRNAs, and they regulate gene expression by binding to mRNAs.
Step-by-step explanation:
The statement about miRNA that is false is: (c) miRNAs are produced from rRNAs. In reality, microRNAs (miRNAs) are not derived from rRNAs; rather, they are initially transcribed in the nucleus from genomic DNA as longer pre-miRNAs. These pre-miRNAs are then processed into shorter, mature miRNA molecules by the action of the enzyme Dicer.
MiRNAs regulate the expression of genes post-transcriptionally by binding to complementary sequences on target mRNAs, often resulting in the degradation or repression of the target mRNA. A single miRNA can regulate many genes, and their altered expression is associated with diseases, including cancer. Small interfering RNAs (siRNAs), on the other hand, can also induce RNA interference (RNAi), but they are distinct molecular entities and do not bind to miRNAs.