Question

Which of these describe some of the similarities and differences between glycogen and starch?

a. Glycogen is less branched than starch and is found in animals.
b. Glycogen is more highly branched than starch and is found in plants.
c. Starch is less branched than glycogen and is found in plants.
d. Starch is more branched than glycogen and is found in animals.

Answer 1

Option (b), Glycogen is a highly branched energy storage molecule in animals, while starch, found in plants, consists of less branched amylose and branched amylopectin molecules.

Step-by-step explanation:

The similarities between glycogen and starch lie in their function as energy storage molecules and their composition being made up of glucose units. However, they have key differences. Glycogen is a highly branched polymer of glucose that serves as energy storage in animals. It is even more highly branched than amylopectin, one of the components of starch, with 8-12 glucose units between branches.

In contrast, starch is a plant storage carbohydrate that consists of two types of molecules: amylose (linear) and amylopectin (branched). Amylose has unbranched chains of glucose units connected by α-1→4 glycosidic linkages, while amylopectin has α-1→4 linkages with α-1→6 branching points. Therefore, the correct statement about similarities and differences between glycogen and starch is that starch is less branched than glycogen and is found in plants.