 Teachers Powered by teachers'domain  RNAi Explained    •
Teacher Resource   • Posted 08.09.07   • NOVA scienceNOW   NOVA
scienceNOW RNAi Explained   • Media Type: Interactive   • Size:
35.7 KB   • Level: Grades 9-12   Source: NOVA scienceNOW: "RNAi
Explained"  This media asset can be found as "RNAi Explained" on
the NOVA scienceNOW web site.   Genes provide the instructions
that cells use to produce, or synthesize, proteins, which are
necessary for the proper functioning of an organism. Protein
synthesis from genes occurs in two basic steps: transcription
and translation. During transcription, instructions contained in
DNA are copied to a single-stranded molecule called messenger
RNA (mRNA). Messenger RNA is subsequently translated into an
amino acid chain (a protein) whose sequence corresponds to that
particular mRNA molecule.  Cells typically perform these steps
flawlessly—producing vital proteins in just the right
quantities, at just the right times. When things go wrong, it is
commonly the result of the