This picture is of a fern with spores on the leaves. There are two types of spores: Spores in plants and algae, and spores in prokaryotes, fungi, and protists. In plants and algae, spores are haploid cells that, without fusing with any other cell, can grow into a multi-cellular organism. The spores in protists, fungi, and prokaryotes are stages of the life cycle that allow the organism to live in harsh environmental conditions. Because ferns are not flowering plants, the fern uses the spores in order to reproduce.