PROTIEN SYNTHESIS
DNA carries the blueprint of all proteins in our bodies, as well as for all other species
. In order for the DNA to be translated into a protein, it first is transcribed into complementary mRNA, which leaves the nucleus to the cytoplasm. In the cytoplasm the message carried in the mRNA is translated into a chain of amino acids, called a polypeptide chain. One gene on the DNA codes for One polypeptide chain. Some proteins have more than one polypeptide chain, therefore more than one gene for its construction. ex the protein insulin has 2 polypeptide chains
The 'epigenetic code' controls gene activity with chemical tags that mark DNA (purple diamonds) and the 'tails' of histone proteins (purple triangles). These markings help determine whether genes will be transcribed by RNA polymerase. Genes hidden from access to RNA polymerase are not expressed.
The 'epigenetic code' controls gene activity with chemical tags that mark DNA (purple diamonds) and the 'tails' of histone proteins (purple triangles). These markings help determine whether genes will be transcribed by RNA polymerase. Genes hidden from access to RNA polymerase are not expressed.





http://www.patana.ac.th/Secondary/Science/c4b/3/chem3.5.htm


TRANSLATION of mRNA chain into a polypeptide chain

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