Answer:
Spirogyra is a green algae having a filamentous structure, which measures about 10-100 micrometer in width. The length of the filament is long and may stretch up to several centimeters. Believe it or not, more than 400 species of spirogyra algae are identified from freshwater habitats. One of the distinctive spirogyra facts is the presence of spiral or helical shaped chloroplast visible under microscope, hence the name. This characteristic feature is used as an identifying attribute for spirogyra genus.