Ulothrix can be described as a

Ulothrix is a green filamentous alga, belonging to class chlorophyceae. The plant body is an unbranched filament consisting cylindrical cells joined end and end. Under favourable conditions, each cell produces zoospores except holdfast. These zoospores are of two types – macrozoospores and microzoospores. The macrozoospores are larger in size and quadriflagellate and the microzoospores are smaller zoospores which may be biflagellate or quadrifagelleate under unfavourable conditions, nonmotile microspores called aplanospores are produced. Sexual reproduction in Ulothrix is of isogamous type.