Which one of the following polymers does not contain glucose units?

Polymers are large molecules composed of repeating structural units. Glycogen, starch, and cellulose are all polysaccharides, meaning they are complex carbohydrates made of glucose monomers. Starch is the primary storage form of glucose in plants [2], while glycogen serves a similar storage function in animals. Cellulose is a structural polymer of glucose found in plant cell walls. In contrast, natural rubber is a hydrocarbon polymer, specifically polyisoprene, composed of isoprene (2-methyl-1,3-butadiene) units rather than sugar molecules. While glucose is the fundamental product of photosynthesis used to synthesize starch [3], rubber belongs to the terpene family and does not contain glucose units in its chemical structure. Therefore, rubber is the only option among the four that is not a carbohydrate polymer.

Sources

1. [1] Science-Class VII . NCERT(Revised ed 2025) > Chapter 10: Life Processes in Plants > 10.2.3 Photosynthesis: in a nutshell > p. 146
2. [2] Science-Class VII . NCERT(Revised ed 2025) > Chapter 10: Life Processes in Plants > 10.2.1 Leaves: the ̒ food factories̓of plants > p. 140
3. [3] Science-Class VII . NCERT(Revised ed 2025) > Chapter 10: Life Processes in Plants > In a Nutshell > p. 150