Fungi are eukaryotic, non-vascular, non-motile and heterotrophic organisms. They may be unicellular or filamentous and reproduce by means of spores. they exhibit the phenomenon of alternation of generation and lack chlorophyll and hence cannot perform photosynthesis. They have chitinous cell wall. Related Theory The vegetative body of the fungi may be unicellular or composed of microscopic threads called hyphae. Hyphae can grow and form a neiwork called a mycelium. Yeasts are unicellular fungi that do not produce hyphae. The cell membrane of a fungus has a unique sterol and ergosterol.