{"id":4955,"date":"2019-05-20T12:49:01","date_gmt":"2019-05-20T12:49:01","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/suny-dutchess-ap1\/?post_type=chapter&p=4955"},"modified":"2019-08-30T13:14:24","modified_gmt":"2019-08-30T13:14:24","slug":"protein-synthesis","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/suny-dutchess-ap1\/chapter\/protein-synthesis\/","title":{"raw":"Genes to proteins: Central Dogma","rendered":"Genes to proteins: Central Dogma"},"content":{"raw":"
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Genes specify functional products (such as proteins)<\/h2>\r\n<\/div>\r\n
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A DNA molecule is divided up into functional units called\u00a0genes<\/strong>. Each gene provides instructions for a functional product, that is, a molecule needed to perform a job in the cell. In many cases, the functional product of a gene is a protein. For example, Mendel's flower color gene provides instructions for a protein that helps make colored molecules (pigments) in flower petals.<\/div>\r\n<\/div>\r\n
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The flower color gene that Mendel studied consists of a stretch of DNA found on a chromosome. The DNA has a particular sequence; part of it, shown in this diagram, is GTAAATCG (upper strand), paired with the complementary sequence CATTTAGC (lower strand). The DNA of the gene specifies production of a protein that helps make pigments. When the protein is present and functional, pigments are produced, and the flowers of a plant have a purple color.<\/div>\r\n
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The functional products of most known genes are proteins, or, more accurately, polypeptides.\u00a0Polypeptide<\/strong>\u00a0is just another word for a chain of amino acids. Although many proteins consist of a single polypeptide, some are made up of multiple polypeptides. Genes that specify polypeptides are called\u00a0protein-coding<\/strong>\u00a0genes.\u00a0Not all genes specify polypeptides. Instead, some provide instructions to build functional RNA molecules, such as the\u00a0<\/span>transfer RNAs<\/a>\u00a0and\u00a0<\/span>ribosomal RNAs\u00a0<\/a>that play roles in translation.\u00a0<\/span><\/div>\r\n<\/div>\r\n
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How does the DNA sequence of a gene specify a particular protein?<\/span><\/div>\r\n
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Many genes provide instructions for building polypeptides. How, exactly, does DNA direct the construction of a polypeptide? This process involves two major steps: transcription and translation.<\/div>\r\n<\/div>\r\n
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