30 likes | 214 Views
3.5.5: Discuss the relationship between one gene and one polypeptide. One gene may code for multiple polypeptides due to alternative splicing (Post transcriptional modification). mRNA from one gene. Introns are transcribed but not translated Exons are transcribed and translated.
E N D
3.5.5: Discuss the relationship between one gene and one polypeptide. One gene may code for multiple polypeptides due to alternative splicing (Post transcriptional modification) mRNA from one gene Introns are transcribed but not translated Exons are transcribed and translated
Post-transcriptional modification, splicing (joining) exons in various combinations example: lymphocyte production of antibodies: millions of different antibody proteins are produced from just a few genes • Some genes do not code for polypeptides at all • some genes code for tRNA (transfer RNA) • not translated into protein • transports amino acids to ribosomes • some genes code for rRNA (ribosomal RNA) • not translated into protein • a component of ribosome structure and function tRNA molecule rRNA molecule