Drosophilia sex determination is controlled through which of the following mechanisms?

Gene regulation in eukaryotes only occurs during the transcription stage of gene expression.

Devoting a few sentences to each, describe the following structures or complexes and their effects on eukaryotic gene expression:

Dicer

Devoting a few sentences to each, describe the following structures or complexes and their effects on eukaryotic gene expression:

RISC

Devoting a few sentences to each, describe the following structures or complexes and their effects on eukaryotic gene expression:

Enhancer

Devoting a few sentences to each, describe the following structures or complexes and their effects on eukaryotic gene expression:

Promoter

How do we know that double-stranded RNA molecules can control gene expression?

How do we know that misregulation of mRNA stability and decay is a contributing factor in some cancers?