Yeast or Saccharomyces cerevisiae is a fungus of class-Ascomycetes. Saccharomyces sp. are widely used in baking and brewing industries. Paramecium and Plasmodium belong to kingdom-Protista, Penicillium belongs to kingdom-fungi. Lichen is a composite organism formed from the symbiotic association of algae and fungi. Nostoc and Anabaena are examples of cyanobacteria or blue-green algae.