Chapter 5, Problem 2TYK

What are three ways monosaccharides differ from one another?

Summary Introduction

To review:

The three ways monosaccharides differ from one another.

Introduction:

Monosaccharides are the simplest form of sugar and are the building blocks or monomers of the carbohydrate macromolecule.

Explanation of Solution

The monosaccharides differ from each other in three ways:

• The monosaccharides differ on the basis of number of C-atoms in the molecule and are classified as triose (3C), tetrose (4C), pentose (5C), and so on.

• The second way in which the monosaccharides differ from one another is the position of the carbonyl group. The carbonyl group can be at the end of the carbon chain (classified as an aldose) or at the position other than the end (in the middle) of the carbon chain (classified as a ketone).

• The next way is the spatial position or arrangement of hydroxyl group in the carbohydrate molecule. When different monosaccharides have the same number of C-atoms in their chain, they differ on the basis of the position of the hydroxyl group. For example, glucose and galactose both are six-carbon sugars, but the difference in the spatial position of the hydroxyl group makes them different from each other in structure as well as function.

Conclusion

The monosaccharides differ on the basis of number of carbon (C) atoms, the position of the carbonyl group, and the spatial position of the hydroxyl group.