According to
Encyclopedia Britannica, the Spirogyra
genus contains around 400 species (2015). These “filamentous algae” are
actually strings of tube-like cells surrounded in a layer of pectin, which
makes them “slippery” to the touch (2015). These fresh-water microorganisms rise
to the surface as large masses of algae when the “oxygen bubbles” they release
during photosynthesis increase their “buoyancy” (2015). The genus name Spirogyra comes from the green, spiral
chloroplasts coursing through the center of the cells (2015). These
microorganisms can reproduce sexually (through “conjugation tubes”) and asexually
as well (2015).