Transcription is the synthesis of mRNA from a DNA template. It is like DNA replication in that a DNA strand is used to synthesize a strand of mRNA. RNA polymerase recognizes a specific base sequence in the DNA called a promoter and binds to it. RNA polymerase unwinds the DNA. RNA polymerase assembles bases that are similar to the DNA strand being copied. The mRNA produced is called the mRNA transcript. The remaining portions of DNA that are translated into protein are called exons. After the intron-derived regions are removed from mRNA, the remaining fragments are spliced to form a mature mRNA transcipt.
References: http://www.nature.com/scitable/topicpage/translation-dna-to-mrna-to-protein-393
http://www.sparknotes.com/biology/molecular/translation/summary.html
Translation
During translation, the cell uses information fro messenger RNA to produce proteins. Like an assembly line worker who attaches one part of another, the ribosome forms a peptide bond between the first and second amino acids. The ribosome then moves to the third codon, where a tRNA molecule brings it the amino acid specified by the third colon.
Reference: http://www.dna-sequencing-service.com/dna-sequencing/translation-dna-2/attachment/translation-dna-2/
Protein Synthesis
During protein synthesis, the transcription and translation of specific parts of DNA form proteins. The polypeptide chain grows until the ribosome reaches a stop codon on the mRNA molecule. When the ribosome reaches a stop codon, it releases the newly formed polypeptide and the mRNA molecule.
Reference: http://www.accessexcellence.org/RC/VL/GG/protein_synthesis.php
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