Question

1. The role of the RNA-induced silencing complex (RISC) in RNA interference is to

a. disrupt gene expression by cleaving mRNAs that are complementary to the guide strand of the RNA duplex that was introduced.

b. cleave the introduced RNA duplex

c. create a passenger strand to bind to the mRNA and keep the mRNA from being translated

d. disrupt gene expression by interfering with mRNA export to the cytoplasm

e. cleave tRNAs to slow the rate of translation

2. Initiation of protein synthesis involves GTP hydrolysis associated with what step?

a. dissociation of the 70S ribosome into 30S and 50S subunits such mRNA and formyl-methionine tRNAf can bind

b. binding of IF2(GTP) to formyl-methionine tRNAf

c. binding of the mRNA and formyl-methionine tRNAf to the 30S subunit of the ribosome

d. binding of the 50S subunit to the 30S subunit with bound mRNA and formyl-methionine tRNAf

e. peptide bond formation between formyl-methionine and the next amino acid coded for by the mRNA

3. How do microRNAs serve to regulate gene transcription?

a. They bind to mRNAs to prevent their transcription.

b. They bind to tRNAs to prevent their use in translation.

c. They bind to Argonaute proteins forming complexes that bind to mRNAs and cleave them

d. They bind to RISC-forming complexes that bind to mRNAs and cleave them

e. They bind to the 30S subunit of the ribosome and block translation initiation