Question

Which one of the following is linear polymer?
(A) Amylopectin
(B) Glycogen
(C) Starch
(D) Amylose

Answer 1

Hint:Linear polymers are those polymers which have long continuous chain without any excess attachments. The long chains are formed by joining the repeating units together. These types of polymers are well packed.

Complete answer:Linear polymers can be defined as the long continuous chains without any excess attachments. The repeating units are joined together to form a long chain. Linear polymers have high densities, high tensile strength and high melting points because these types of polymers are well packed. The examples of linear polymer are polythene, poly – vinyl chloride etc.Now, look at the options given in the question which are amylopectin, glycogen, starch and amylose we will look at these one by one –Amylopectin is the water – soluble polysaccharide and it is highly branched polymer of $\alpha - $ glucose units found in plants.The multibranched polysaccharide of glucose that serves as a form of energy storage in animals, fungi and bacteria is known as glycogen.Starch can be defined as polymeric carbohydrate which consists of numerous glucose units which are joined by glycosidic bonds. This polysaccharide is produced by most green plants as energy storage.Amylose is the polysaccharide which is made of $\alpha - D - $ glucose units. This is bonded with each other through $\alpha \left( {1 \to 4} \right)$ glycosidic bonds which is the linear polymer.

Hence, the correct option is (D).

Note:Amylose consists of two types of molecules which are linear and helical amylose and the branched amylopectin. So, it is branched polymer which are formed when linear chains of polymer form branches.