In this situation, translation begins at the 5' end of the mRNA while the 3' end is still attached to DNA. In all types of cells, the ribosome is composed of two subunits: the large (50S) subunit and the small (30S) subunit (S, for svedberg unit, is a measure of sedimentation velocity and, therefore, mass).
The most common types of nuclear power plants use water for cooling in two ways: 1  To convey heat from the reactor core to the steam turbines. 2  To remove and dump surplus heat from this steam circuit.
Plants that require the use of cooling water account for a little more than 70% of all the electricity in the nation and nearly 60% of the electric generating capacity. Withdrawal is the amount of water a power plant takes in from a source such as a river, lake, or ocean for the purpose of cooling steam.