How are fructose different from glucose?

They have a double - bonded oxygen in different locations.

The are simmilar and different

Explanation:

Even though both glucose and fructose are monosaccharides and have the same molecular formula, glucose has a six member structure and fructose has a five member structure.

Also, fructose has a lower glycemic index than the glucose which means, it provides less amount of energy per molecule than the glucose.