NANP Board Practice Exam

What polysaccharide reinforces plant-cell walls and can be classified as dietary or functional fiber?

1. Cellulose

2. Dietary fiber

3. Glucose

4. Hemicellulose

The correct answer is: Cellulose

Cellulose is indeed the correct answer as it is a type of polysaccharide that provides structural support to plant-cell walls. It is classified as dietary fiber because it is not digestible by human enzymes, allowing it to pass through the digestive system and contribute to overall gut health. Additionally, cellulose serves a functional purpose in the diet, enhancing bulk and promoting regular bowel movements. Other options such as dietary fiber are a broader category that includes various types of fibers, but cellulose specifically refers to the actual polysaccharide with a defined structure reinforcing plant cells. Glucose, while fundamental as a simple sugar, does not serve as a structural component of cell walls. Hemicellulose, on the other hand, is another component of plant cell walls but differs in structure and composition from cellulose and does not solely represent the reinforcement aspect found in cellulose.