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Starting & Stopping Translation. Joohee Kim Sec. III IB Biology. Genetic Information. Genetic information flow can be divided into 3 stages 1. Replication : DNA is duplicated 2. Transcription : information from DNA is transferred to RNA
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Starting & Stopping Translation Joohee Kim Sec. III IB Biology
Genetic Information • Genetic information flow can be divided into 3 stages • 1. Replication: DNA is duplicated • 2. Transcription: information from DNA is transferred to RNA • 3. Translation: information in mRNA is used to build polypeptides
Translation: Process of Protein Synthesis • 1.Initiation: 2 ribosomal subunits assemble with mRNA • 2.Elongation: amino acids are brought to ribosome and are added to growing polypeptide • 3.Termination: occur when ribosome reaches stop codon
How is Reading Frame Chosen? • Reading Frame: Non-overlapping set of three-nucleotide codons in RNA • Genetic code contains signals for starting and stopping translation. • Start Codon: AUG • Stop Codon: UAA, UAG, UGA
Start Codon & Stop Codons • Start Codon: AUG • => signal for starting translation • Stop Codon: UAA, UAG, UGA • => signal for stopping translation