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Protein Synthesis. Protein Synthesis. Transcription Translation. Transcription. Process by which the DNA code ( Coding Strand ) is copied onto a strand of RNA Three stages. RNA nucleotides. RNA polymerase. A. C. C. A. T. T. A. U. T. C. G. T. U. G. A. C. A. U. C. C. A.
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Protein Synthesis • Transcription • Translation
Transcription • Process by which the DNA code (Coding Strand) is copied onto a strand of RNA • Three stages
RNA nucleotides RNA polymerase A C C A T T A U T C G T U G A C A U C C A C C A G A T T T A G G Direction of transcription Template Strand of DNA Figure 10.9A Newly made RNA
RNA polymerase DNA of gene Promoter DNA Terminator DNA Area shown In Figure 10.9A Growing RNA Completed RNA RNA polymerase Figure 10.9B 1 Initiation 2 Elongation 3 Termination
Initiation • RNA polymerase II attaches to DNA • Enzyme unwinds the portion of DNA that codes for the needed protein
Elongation • Free RNA nucleotides will bond to the exposed bases of the DNA strand • Synthesizes a complimentary strand of RNA
Termination • Occurs when the RNA polymerase II reaches the terminator region • New RNA is released from the DNA
Processing a mRNA • Shortens the mRNA • A methyl guanine cap is placed at the starting end of the mRNA • A poly A tail forms
Processing a mRNA • Parts of the mRNA are cut out • Cut ends are spliced back together • INTRON • EXONS
Exon Intron Exon Intron Exon DNA Transcription Addition of cap and tail Cap RNA transcript with cap and tail Introns removed Tail Exons spliced together mRNA Coding sequence Nucleus Cytoplasm Figure 10.10