Transcription_And_Protein_Synthesis

Transcription And Protein Synthesis A gene is a nucleotide sequence on a strand of DNA. The “one gene – one polypeptide” hypothesis states that a single gene provides the code for a specific enzyme, protein or polypeptide. This means the gene provides the instructions to build a polypeptide but it does not build it directly; it needs RNA as a bridge. The four nucleotides adenine, thymine/uracil, guanine and cytosine are the monomer bases for DNA and RNA (nucleotides only fit to a complementary nucleotide; A-T/U and C-G; this is called the base-pairing rule). In polypeptides and proteins the monomer bases are the 20 amino acids. Since the information is encoded in two different chemical languages, transcription and translation are used to get from one language to the other. Transcription is the synthesis of RNA under the direction of DNA. Because both DNA and RNA use the same language, the transcription phase is just the copying of information from one molecule to the other. In order for the copy to be made, the DNA must unwind and separate. An enzyme pries apart the two strands of DNA and attaches the RNA nucleotides to their complementary base-pairs along the DNA template. This enzyme is called the site, trna, rna, dna, amino, mrna, end, called, polypeptide, acid, transcription, nucleotides, codon, polymerase, enzyme, translation, subunit, sequence, ribosome, ribosomal, one, moves, gene, complementary, 3’, until, strand, stop, start, nucleus, nucleotide, next, molecule, leaves, large, continues