The Functions of DNA
2. Protein synthesis “Central dogma” (main idea) of molecular biology: DNARNAprotein We already know that proteins do the work to make all your traits, which make you YOU.
What is RNA? RiboNucleic Acid How is that different from DNA? Ribo- vs. Deoxyribo-
RNA vs. DNA Single strand Double strand
RNA vs. DNA con’t. Different sugars
RNA vs. DNA con’t. Base difference: DNA: thymine RNA: uracil (U)
What is the function of RNA? To carry the genetic message from the nucleus to where it will be used in the cytoplasm
Protein Synthesis Part I: Transcription DNARNAprotein
Transcription 1.A gene on the DNA molecule unwinds and unzips
Transcription 2. RNA bases are matched to unraveling DNA strand, using RNA polymerase
Transcription 3. RNA strand (called messenger RNA or mRNA) detaches from DNA and leaves nucleus to travel into cytoplasm
imat/molgenetics/transcription.swf
Why is transcription necessary? DNA is double stranded and too big to leave nucleus through pores DNA is the all-important master template and must stay protected. RNA is disposable
Practice transcription TAC GAA CGA GTG AUG CUU GCU CAC