Fun Fact: Every human spent about half an hour as a single cell

1. Fun Fact: Every human spent about half an hour as a single cell Objective 3: Summarize the process of protein synthesis Homework: Transcription & Translation Diagrams Journal #4: In DNA, which nucleotide pairs with Adenine? Guanine? Which DNA nucleotide is not represented in RNA?

2. Gene Activation & Protein Synthesis Pgs. 80-84

3. Gene Activation • Each DNA molecule houses thousands of genes tightly coiled around histones • Genes have instructions to make proteins • Genes uncoil and histones are removed when a gene becomes active • Promoters: start each gene • Histones uncoil • 2 complimentary DNA strands unzip • RNA polymerase binds to the promoter • Transcription occurs • Messenger RNA is made • mRNA leaves goes to the cytoplasm to synthesize protein

5. Transcription of mRNA • Step 1: DNA strands separate and RNA polymerase attaches to the template strand (complimentary triplets- codons) • Step 2: RNA polymerase begins attaching the complimentary nucleotides to the mRNA chain • Adenine, Guanine, Cytosine, & Uracil (instead of Thymine as in DNA) • Step 3: At the stop codon the mRNA detaches from the DNA strand

8. RNA Processing • Introns- nonsense regions of mRNA • Exons- coding segments • Before the mRNA leaves the nucleus the introns must be snipped out and the exons spliced together • Regulation of this “editing” is not yet explained by science

9. TranslationAKA: Protein Synthesis • Reading the code from the mRNA to make a protein • Starts with codon-AUG for start • The anticodon UAC brings the amino acid methionine to start the amino acid chain • Ribosomes (in the cytoplasm) join the amino acids together as directed by the tRNA to form the directed protein • Ends with a stop codon

11. http://www.youtube.com/watch?v=D5vH4Q_tAkY