In which of the following polysaccharides, monomers are linked by a beta-glycosidic bond
**Core Concept:** Polysaccharides are complex carbohydrates formed by the association of monosaccharides, which are simple sugars. Beta-glycosidic bonds are covalent bonds that connect monosaccharides in a specific configuration.
**Why the Correct Answer is Right:** Dextran is a biopolymer composed of glucose monomers linked together by beta-glycosidic bonds. The beta configuration ensures that the resulting polysaccharide has a linear structure.
**Why Each Wrong Option is Incorrect:**
A. In amylose, monomers (glucose) are linked by alpha-glycosidic bonds. This results in a helical structure, not a linear one.
B. Maltose, a disaccharide, is not considered a polysaccharide. It consists of two glucose monomers linked by an alpha-glycosidic bond.
C. In chitin, monomers are linked by beta-glycosidic bonds, but chitin is a structural component of fungal cell walls, not a soluble polysaccharide.
D. In cellulose, monomers (glucose) are also linked by beta-glycosidic bonds, but cellulose forms microfibrils due to hydrogen bonding, which contributes to its characteristic properties.
**Clinical Pearl / High-Yield Fact:** Understanding polysaccharides and their structures is crucial for understanding their biological roles and properties. Dextran, being a soluble beta-glucan, is used as a hemostatic agent in clinical practice to control bleeding.
**Correct Answer:** .