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.
Safeguards for Faulty Mitosis. Mitosis is a multi-step process with checkpoints to make sure things are going properly. If a cell detects that something has gone wrong during mitosis, the first thing it does is to stop the process. The three major checkpoints during mitosis -- the G1, G2 and mitotic spindle checkpoints -- all provide the cell with an opportunity to intervene if something goes wrong so that it can fix the problem.