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How are starch and cellulose alike as glucose polymers?

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Diagram illustrating a homopolymer arrangement using polyvinyl chloride as an example, showing a chain of identical repeating vinyl chloride units with the chemical structure highlighted. — polymer Industrial polymers are synthesized from simple compounds joined together to form long chains. For example, polyvinyl chloride is an industrial homopolymer synthesized from repeating units of vinyl chloride.

Starch and cellulose are alike in that they are both homopolysaccharides composed exclusively of glucose units. As polymers, they are both built from the same fundamental sugar building block, though they differ significantly in their chemical linkages, biological functions, and physical structures.12

The primary similarities and key distinctions are:

Composition: Both are polymers formed from glucose molecules.12
Linkage Differences: Starch (specifically its components amylose and amylopectin) utilizes $α, 1 \to 4$ linkages, whereas cellulose is composed of glucose units joined by $β, 1 \to 4$ linkages.1
Function: Starch serves as a food storage polysaccharide in plants, while cellulose acts as a structural component, providing stability to plant cell walls.12
Structure: Cellulose forms large, linear, and often crystalline fiber-like arrangements that are highly stable and insoluble in water. In contrast, starch consists of both linear (amylose) and branched (amylopectin) components, which are utilized by organisms as an energy source.21