Fructans are polymers formed from which sugar?

• A. Glucose
• B. Sucrose
• C. Lactose
• D. Fructose

Answer: (D)

Fructans are polymers formed from fructose units linked together. The defining feature is that the repeating building block is fructose, so the polymer’s chain is made entirely of fructose molecules. In plants, fructans like inulin store energy, illustrating this fructose-based structure. Sucrose and lactose are disaccharides (glucose–fructose and galactose–glucose, respectively) and are not polymers of a single sugar, so they don’t describe fructans. Therefore, fructose is the sugar from which fructans are formed.