Question

Starch is composed of two polysaccharides namely:

• A. amylopectin and glycogen
• B. amylose and glycogen
• C. amylose and amylopectin
• D. amylose and amylopectin and glycogen

Answer 1

Answer: (C)

amylose and amylopectin

Amylose and amylopectin are polysaccharides of starch. Starches are glucose polymers in which glucopyranose units are bonded by $\alpha$-linkages. It is made up of a mixture of amylose (15%-20%) and amylopectin (80%-85%). Amylose consists of a linear chain of several hundred glucose molecules and Amylopectin is a branched molecule made of several thousand glucose units. Starches are insoluble in water. They can be digested by hydrolysis, catalyzed by enzymes called amylases, which can break the $\alpha$-linkages (glycosidic bonds).