As indicated in the figure, the ring and chain forms are in equilibrium. To reach the chain form from the ring configuration, the bond between the ring oxygen and carbon atom number 5 breaks, the oxygen becomes double-bonded to carbon atom number 1 and the OH group on carbon No. 1 moves to carbon No. 5. This transformation does not occur so simply, however. The two isomers are end states of four intermediate molecular configurations.
Numbering of the carbon atoms is helpful in following reactions of glucose. For example, if an orthophosphate ion replaces the hydroxyl group on top of the ring structure in Fig. 11.2, the reaction would be written as:
indicating that the phosphate group is attached to carbon atom 6 of the glucose molecule1
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Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.