Question

why this happen in plant

Answer 1

Glucose, fructose and galactose are the three dietary monosaccharides. Glucose and Fructose are simple monosaccharides found in plants. A monosaccharide is the basic unit of carbohydrate and the simplest form of sugar, glucose are aldose and Fructose are ketose.

If the carbonyl is at position 1 (that is, n or m is zero), the molecule begins with a formyl group H(C=O)-, and is technically an aldehyde. In that case, the compound is termed an aldose. Otherwise, the molecule has a keto group, a carbonyl -(C=O)- between two carbons; then it is formally a ketone, and is termed a ketose. Ketoses of biological interest usually have the carbonyl at position 2.

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