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Protein Synthesis. Transcription and Translation. Transcription. Begins at the start codon “ATG” and stops with “TAA”,”TAG”, or “TGA” mRNA binds with the bases to form the mRNA code. mRNA. Known as messenger RNA RNA stands for Ribosenucleic acid (ribose sugar)
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Protein Synthesis Transcription and Translation
Transcription • Begins at the start codon “ATG” and stops with “TAA”,”TAG”, or “TGA” • mRNA binds with the bases to form the mRNA code
mRNA • Known as messenger RNA • RNA stands for Ribosenucleic acid (ribose sugar) • Binds with the antisense or template strand of DNA • Has a sugar – phosphate backbone to hold bases in place
Create the mRNA strand Fill in the rest of the mRNA code:
Compare DNA and mRNA Compare: name, size, composition (what it is made of), location, bases, and function
Summarize Transcription • DNA unzipps Helpful website: DNA to mRNA Transcription
Translation Ribosome
tRNA • Looks like a “t” • Matches up with the mRNA code and attaches the corresponding amino acid
1. Initiation • mRNA binds to a ribosome at the 5’ end • Slides down the mRNA until it encounters the AUG or start codon • The AUG codon for methionine
2. Elongation • tRNA matches the next codon on the mRNA • The amino acid chain (the protein) is linked to the newest amino acid • The old tRNA is released • The ribosome moves down the mRNA strand to the next codon
3. Termination • The stop codon is reached on the mRNA • Either UAA, UAG, or UGA (remember U replaces T in RNA) • The protein is released from the ribosome • The mRNA is released from the ribosome
Try It Out • Go to the website and try to create a protein chain from the DNA code given: • Transcribe and Translate DNA • In your journal, highlight 3 things you learned today and one question you have.