Question

What structural difference accounts for the functional differences between starch and cellulose?A) Starch can be digested by animal enzymes, whereas cellulose cannot.B) Starch and cellulose differ in the glycosidic linkages between their glucose monomers.C) Starch is a polymer of glucose, whereas cellulose is a polymer of fructose.

Answer 1

Answer:

Option (B).

Explanation:

Carbohydrates is one of the most important biomolecule that plays an important role in the living organism. Carbohydrates are made of monosaccharides sugars linked through glycosidic linkage.

Starch is made of the glucose residues in which the linear glucose residues are linked through alpha glycosidic linkages. Cellulose is the polymers of glucose linked through the beta glycosidic linkage. Hence, they are differ in the glycosidic linkage.

Thus, the correct answer is option (B).

Answer 2

Answer:

Both starch and cellulose are glucose polymers, but the glycosidic linkages in these two polymers differ, as shown in Figure 5.7. Glucose can have two slightly different ring structures. When glucose forms a ring, the hydroxyl group attached to the number 1 carbon is positioned either below (alpha)or above (beta) the plane of the ring. In starch, all the glucose monomers are in the alpha configuration (Figure 5.7b). In cellulose, all the glucose monomers are in the beta configuration. As a result, every other glucose monomer is "upside down" with respect to its neighbors (Figure 5.7c). The differing glycosidic linkages in starch and cellulose give the two molecules distinct three-dimensional shapes, leading to key functional differences.

Explanation: