Your heart then pumps it through your body to provide oxygen to the cells of your tissues and organs. As the cells use the oxygen, carbon dioxide is produced and absorbed into the blood. Your blood then carries the carbon dioxide back to your lungs, where it is removed from the body when you exhale.
DNA polymerase has 5'-3' activity. All known DNA replication systems require a free 3' hydroxyl group before synthesis can be initiated (note: the DNA template is read in 3' to 5' direction whereas a new strand is synthesized in the 5' to 3' directionâthis is often confused).
In a eukaryote, DNA never leaves the nucleus, so its information must be copied. This copying process is called transcription and the copy is mRNA. Transcription takes place in the cytoplasm (prokaryote) or in the nucleus (eukaryote). The transcription is performed by an enzyme called RNA polymerase. To make mRNA, RNA polymerase: Binds to the DNA strand at a specific sequence of the gene called a promoter.