The process of RNA transcription has some similarities to DNA replication (e.g., synthesis occurs in the 5' to 3' direction), but it also has some important differences. First, only one strand of DNA is used as a template for RNA synthesis. Second, ribonucleotides are used instead of deoxyribonucleotides. Finally, not all DNA in a genome is transcribed at once. Rather, via the action of transcription factors and gene regulation, only selected genes are transcribed at a given time. Be sure that you understand the basic aspects of this process.
Protein translation is the process by which messenger RNA (mRNA) supplies the necessary information for the synthesis of proteins. There are three basic components to a cell's translational machinery: mRNA, tRNA, and ribosomes. Messenger RNA provides the template that will be used for ordering the correct sequence of amino acids. Fidelity of the translational process is assured, in part, by the fact that each amino acid has its own transfer RNA. Transfer RNA (tRNA) is found with an appropriate amino acid. For example, a tRNA that has an anticodon of "UAC" will bind to the triplet on the mRNA with the complimentary sequence "AUG." Thus, each tRNA delivers the appropriate amino acid to the ribosome; ordering of amino acids is determined by the linear arrangement of the genetic code. Be sure that you understand the relationship between these three components of the cell's translational machinery.