Characteristics of Fungi

General Characteristics Of Fungi

• The vegetative body of fungi may be either unicellular (yeast) or multicellular.
• Groups of fungi are formed of elongated cells which form filaments called hyphae. These hyphae form a diffuse association of cells. This association of cells is referred to as Mycelium, a word that represents the body of the fungus.
• Fungi produce reproductive hyphae which bear numerous spore-containing structures called sporocarp. This structure is purely for reproductive purposes and has nothing to do with the normal growth and development.
• Like plants, fungi also grow attached to their substratum. They are non-motile and lack locomotory organs like flagella, except for chytrids, which are motile gametes with flagella.
• The surface of fungi is folded into numerous ridges called gills (found under the cap of mushrooms), which are actually adaptations to increase the surface area. They are used for disposal of spores and are extremely important in taxonomy for species identification. 

• Fungi are mostly eukaryotic multicellular organisms i.e., they have many cells in their bodies, each cell complete with membrane-bound cell organelles.
• Most of the fungal cells are coenocytic; there is no distinction between cells; the nuclei are distributed throughout the filament.
• Ascomycetes and basidiomycets have filaments that are septate, with numerous septa which separates individual cells from each other. The features of septa are different in different fungi and thus, they have taxonomical importance as well.
• The filaments have cytoplasm and large vacuoles.
• The cell wall of a fungal cell is made of chitin, unlike the cell walls of plants which are made of cellulose and lignin.
• Fungi are non-vascular organisms. 

• Fungi are heterotrophic; they depend on others for food.
• Unlike plants and animals, fungi first digest the food and then ingest it. This is possible with the help of exoenzymes. Fungi store food as glycogen like animals do.
• The ergosterol found in fungal cells has similar functions to that of mammalian cholesterol.
• Saprophytic fungi depend on non-organic materials for food. They play an important role in recycling of nitrogen, carbon and other essential mineral nutrients.
• Parasitic fungi thrive on organic food derived from a range of hosts including plants and animals.
• Symbiotic relationships are formed between certain types of plants and fungi. Symbiotic associations of plant roots and fungi are called mycorrhizae while fungal associations with plants or cyanobacteria are called lichens. 

• Fungi can cause diseases in plants and animals, including human beings.
• Fungi are capable of damaging all kind of things, except for some pesticides and plastics.
• They can compete with other pathogens for food by following the complete exclusion principle. According to this, two groups of organisms competing for the same resource cannot co-exist. This characteristic feature of fungi is used for biological pest control.
• Fungi cause many diseases in human beings. Athlete’s Foot is one such disease caused by Trichophyton which includes symptoms like itching, scaling and flaking of the affected skin. Candidiasis or thrush is another serious fungal infection which ranges from superficial infection to systemic and is a potentially life-threatening disease.
• Fungal infections occur in animals and plants too. Such infections in agricultural plants are a major threat faced by farmers across the globe.
• Fungal infections generally occur in moist and warm areas like the area under clothes and shoes. The infections initially occur on the skin surface and then penetrate into deeper parts. They may enter into the body through cuts and injuries as well. 

• Fungi have two kinds of reproduction – sexual and asexual.
• Asexual reproduction is done by means of spores. Spores can remain dormant for long time and they germinate during favorable conditions.
• Sexual reproduction involves combination of two compatible nuclei or gametes followed by mitotic division.
• Sex organs are called gametangia and they may be distinguished into male and female, depending on the gametes present. Sometimes, both male and female gametes are present in the same gametangia. 
• Homothallic mycelia do not need other mycelium for sexual reproduction; both male and female gametes are present in them.
• Heterothallic mycelia need other mycelia for sexual reproduction because though both male and female gametes are present in the same mycelium, they are not compatible.