[tweetiepooh]

My Biochemistry is very old. This could be out of date now.

D-Glucose (chiral has a L and D form) is the most abundant organic molecule in the biosphere.
It is broken down in a process called glycolysis (sweet splitting).
D Glucose -> Glucose 6 Phosphate (G6P) -> Fructose 6 Phosphate (F6P)-> Fructose 1,6 Diphosphate


And then down a further chain of reactions to the TCA and then on further. The net goal is production of molecules like ATP which is a energy source for cells.


Sucrose (what we call sugar) is glucose attached to fructose. We would break that down to glucose and fructose. In the cell F6P and G6P can be interconverted or joined to get Sucrose P and then Sucrose.


Fructose can be metabolised in the liver to Fructose 1 Phosphate (F1P) but we don't have the ability to change that to F6P. We can get fructose intolerance in some cases. One of the products we can break F1P to is glycerol which can make fat.