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There are no tRNAs for stop codon. what does this mean?

Polyeptide synthesis is terminated when a nonsense codon of mRNA reaches the A-site on the larger subunit of ribosome. There are three nonsense codons- UAA, UAG and UGA. These codons are not recognised by any of the tRNAs. This brings the termination of polypeptide synthesis as no more aminoacyl tRNA reaches the A site. The P site tRNA is hydrolysed and the completed polypeptide is released in the presence of GTP dependent release factor. 

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Stop codonsare UAA , UGAand UAG.The end of translation occurs when the ribosome reaches one or more of these stop codon. There are no t-RNA molecules with anticodon for Stop codons. Therefore translation comes to an end , protein is released.
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