siRNA and miRNA Pathways Quiz

What is the typical length of mature siRNA and miRNA molecules?

• 50-60 nucleotides

• 10-15 nucleotides

• 21-23 nucleotides

• 100-120 nucleotides

Which enzyme processes long double-stranded RNA into siRNA?

• Drosha

• Dicer

• RNase H

• RNA polymerase

Where is the Drosha enzyme active during miRNA processing?

• Cytoplasm

• Mitochondria

• Nucleus

• Ribosome

Which of the following is true about siRNA?

• Binds to mRNA with partial complementarity

• Derived from endogenous hairpin precursors

• Binds with perfect complementarity and cleaves mRNA

• Always enhances translation

The RNA-induced silencing complex (RISC) is responsible for:

• DNA replication

• Protein folding

• mRNA degradation or translational repression

• Ribosomal assembly

Which Argonaute protein is primarily involved in mRNA cleavage in humans?

• Ago1

• Ago2

• Ago3

• Ago4

What is the function of the guide strand in RNA interference?

• Activates ribosomes

• Directs RISC to complementary mRNA

• Forms a hairpin structure

• Synthesizes proteins

Which of the following statements best describes miRNA action?

• Cleaves DNA in the nucleus

• Enhances transcription

• Represses translation or degrades mRNA

• Synthesizes complementary RNA

How is the pre-miRNA transported from the nucleus to the cytoplasm?

• Ribosomes

• Exocytosis

• Exportin-5

• Passive diffusion

What distinguishes siRNA from miRNA functionally?

• siRNA inhibits transcription, miRNA enhances it

• siRNA leads to mRNA cleavage, miRNA usually represses translation

• siRNA is longer than miRNA

• miRNA targets DNA, siRNA targets proteins