The role of flagella in prokaryotic organisms is to provide motility, allowing these microorganisms to move towards favorable environments or away from harmful substances. Flagella are long, whip-like structures that extend from the cell surface, rotating like a propeller to propel the organism through liquid. In bacteria, flagella are composed of a protein called flagellin and can be located at various positions on the cell, influencing their movement patterns. Flagellar movement is crucial for survival, assisting in nutrient acquisition and evasion from predators or adverse conditions.