Nostoc reproduces asexually by binary fission.
YES! Their role as a nitrogen fixer in terrestrial ecosystems allow them to maintain symbiotic relationships with many other organisms including mosses, ferns, and fungi to form lichens.
Of course! Some types of Nostoc are actually edible, and are even considered delicacies in some regions; in China during holidays a black hairlike vegetative species, Nostoc flagelliforme, is eaten.
However, these algae can also cause problems for humans by growth on sport turf and buildings, and can lead to unpleasant odors in drinking water. Some extracts from Nostoc are known to be human pathogen inhibitors, and may in the future be valuable to scientists for medical research.
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