PROTEIN SYNTHESIS

 What does protein synthesis mean?  What do proteins do?

3 STEPS TO MAKE PROTEINS  Transcription=Making RNA from DNA  RNA processing  Translation=Making protein from RNA

RNA  We have talked all about DNA, but what is RNA?  RNA carries instructions from DNA to make proteins

HOW DOES RNA DIFFER FROM DNA? 1)DNA sugar is deoxyribose; RNA sugar is ribose 2)DNA has thymine; RNA has uracil 3)DNA is double stranded; RNA is single stranded ACTIVITY: Take a moment to draw a Venn diagram showing the similarities & differences between DNA & RNA

TRANSCRIPTION & TRANSLATION OVERVIEW

HOW TO MAKE RNA MOLECULE  Strand of DNA used to copy complimentary RNA strand  Controlled by enzyme called RNA polymerase  Enzyme separates the DNA double helix and begin reading one of the strands of DNA  That one strand of DNA is used to make pre-mRNA (messenger RNA)  If the strand of DNA being used to make mRNA is:  T A C C G T G A A T  What is the complimentary pre-mRNA strand that is made?

LET’S PRACTICE SOME MORE!  Complete only the complimentary pre-mRNA strand on the worksheet!

RNA PROCESSING  pre-mRNA strand has to be cleaned up to become mRNA  2 types of sections  Introns=sections that are taken out  Exons=sections that are kept and come together to form a mature mRNA strand

MAKING PROTEIN

tRNA  tRNA=transfer RNA  Brings the parts to make a protein based on the mRNA instructions  Proteins are strings of molecules called amino acids  tRNA gets the correct amino acid to the mRNA to build the string

CODONS  Groups of three nucleotides carried on the mRNA strand  Codes for the anticodon carried on tRNA

LET’S TAKE A LOOK AT THE ENTIRE PROCESS!

THE ENTIRE PROCESS (TRANSCRIPTION & TRANSLATION)