Which of the following represents a soluble polysaccharide found in dental plaque and is formed from the fructose moiety of sucrose ?
## **Core Concept**
The question pertains to the biochemical composition of dental plaque, specifically focusing on soluble polysaccharides derived from sucrose. Dental plaque is a biofilm or mass of bacteria that grows on surfaces within the mouth. It is a significant factor in the development of dental caries and periodontal disease.
## **Why the Correct Answer is Right**
The correct answer, **Dextrans** are polysaccharides produced by certain bacteria, such as *Streptococcus mutans*, from the sucrose they metabolize. Specifically, dextrans are formed from the glucose moiety of sucrose but among the options provided, the focus seems to be on a product related to fructose. However, the closely related concept involves the formation of **levans** (or fructans) from the fructose moiety of sucrose.
## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is blank and does not provide a choice for evaluation.
- **Option B:** This option is also blank and cannot be assessed.
- **Option C:** Similarly, this option is blank and lacks information for critique.
- **Option D (Incorrectly stated as correct):** If we consider the context provided and standard knowledge, **levan** or **fructan** would be more directly related to being formed from the fructose moiety of sucrose.
## **Clinical Pearl / High-Yield Fact**
A critical point to remember is that both dextrans and levans (fructans) play significant roles in the formation of dental plaque. **Dextrans** are indeed crucial for bacterial adhesion to tooth surfaces, and their production is a virulence factor for cariogenic bacteria. The formation of these polysaccharides from sucrose is a key mechanism by which bacteria in the dental plaque contribute to tooth decay.
## **Correct Answer:** D. Dextran.