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General Biology Notes TRANSLATION A.K.A. PROTEIN SYNTHESIS. Translation Definition:. the process of converting or translating the information in mRNA into a sequence of amino acids that makes up proteins. NOTE:. Before translation can begin, transcription of the DNA into mRNA must occur.
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Translation Definition: • the process of converting or translating the information in mRNA into a sequence of amino acids that makes up proteins.
NOTE: • Before translation can begin, transcription of the DNA into mRNA must occur.
There are three types of RNA involved in protein synthesis: mRNA, rRNA and tRNA
3 steps: 1. Initiation: mRNA attaches to the ribosome (rRNA). (The rRNA slides along the mRNA like a bead on a string.)
rRNA “reads” the mRNA in groups of three nucleotides called a codon. • Translation always begins with a special codon (AUG) called the initiator or startcodon.
NOTE: • there are 20different amino acids and 64different codons. Each amino acid may have morethan one codon but each codon specifies for only oneamino acid.
2. Elongation: • Transfer RNA (tRNA) carries or “taxis”a specific amino acid determined by the anticodonto the ribosome. • The anticodon of tRNA pairs with the complementary codon on mRNA.
As the tRNA’s line up the amino acids, peptide bonds form between amino acids linking them into a protein.
3. Termination: • the protein is released from the ribosome when a “stop” codon is reached. There are three special “stop” codons: UAA, UAG and UGA