Why does gluten make dough elastic?

Gluten makes dough elastic because it is composed of proteins—specifically gliadin and glutenin—that form a continuous, chainlike network when flour is mixed with water.12

This protein network acts as the structural foundation of the dough. Its elasticity allows the dough to trap carbon dioxide gas produced during the leavening process, enabling the dough to expand and rise. The strength and elasticity of this network are directly influenced by the protein content of the flour; for instance, hard wheat flours contain higher protein levels, which create a stronger structure suitable for breads, while soft wheat flours produce a more delicate, less elastic texture ideal for cakes and pastries.123