NANP Board Practice Exam

Which type of carbohydrates are glucose, fructose, and galactose considered?

1. Complex carbohydrates

2. Disaccharides

3. Monosaccharides

4. Polysaccharides

The correct answer is: Monosaccharides

Glucose, fructose, and galactose are classified as monosaccharides because they are the simplest form of carbohydrates. Monosaccharides consist of single sugar units that cannot be hydrolyzed further into smaller carbohydrate molecules. They serve as the basic building blocks for more complex carbohydrates. Monosaccharides are characterized by their straightforward chemical structure, typically comprising a single ring or chain of carbon atoms with attached functional groups, which is essential for their role in energy metabolism within the body. For example, glucose is a vital source of energy for cells, while fructose is primarily found in fruits and honey, and galactose is a component of lactose, the sugar found in milk. In contrast, the other types of carbohydrates mentioned, such as complex carbohydrates, disaccharides, and polysaccharides, involve multiple sugar units. Disaccharides are formed by the bond of two monosaccharides, while polysaccharides consist of long chains of monosaccharide units. Therefore, glucose, fructose, and galactose stand out as the simplest carbohydrates, making their classification as monosaccharides the accurate choice.