The UK's most valuable monument is deemed to be the 1,000-year-old Tower of London, which is worth an estimated Â£56billion to the British economy and came it at number five in the list of European list. Its value is six times more than its nearest rival the Colosseum in Rome, which is valued at Â£72billion.
Cell cycle checkpoints are control mechanisms in eukaryotic cells which ensure proper division of the cell.
Checkpoint controls in eukaryotic cells. Checkpoints serve to monitor the order of events in the cell cycle and ensure that a cell cycle event occurs only after the completion of a prior event (Weinert and Hartwell, 1989).