Fungi are a group of organisms that play a vital role in the natural world. Fungi are the scavengers of the natural world. They (fungi) range in complexity from simple single-celled organisms like yeast to complex multi-cellular organisms like mushrooms.
The fungus is abundant and omnipresent in the natural world. The air we breathe, the water we drink and the soil, all contain fungus. Apart from being natural scavengers, the fungus is also important in medicine. Fungus cause many diseases. The most common infections caused by fungus include skin and hair infections. However, the fungus can also cause serious infections like pneumonia and bloodstream infections, especially in persons with compromised immunity.
What is unique about fungus?
Till 1969, fungi were considered to be a part of the plant kingdom. However, research showed that fungi are different from other animals and plants. The cell walls of fungi contain a substance- chitin. The cell wall or membrane of plants and animals does not contain chitin. Therefore, fungi are now a separate kingdom.
How do fungi derive their nutrition?
Like other animals, fungi are also heterotrophs. That means that they (fungi) derive their nutrition from the natural world. As discussed before, a fungus is the first scavengers of the natural world. Therefore, you are likely to see them near rotting organic matter, like waste dumps or even in your garden.
What are the types of fungi?
There are three major types:-
Filamentous Multicellular moulds like Aspergillus or Rhizopus: – The basic unit of moulds is the hyphae. The hypha is a long filament that grows and repeatedly divides, forming a bunch of intervened filaments- the mycelium.
Mushrooms- multicellular, filamentous fungus that form large fruiting bodies: – Mushrooms are also made up of hyphae. The body of the mushrooms contains many hyphae that are tightly packed to form the umbrella-like structure that grows overground.
Most of the medically important fungus belong to the category of yeasts or moulds. On the other hand, the commercially important fungus belongs to the class of mushrooms (not in the strictest sense, fungi like yeast are also important commercially, like in bakeries and breweries).
How do fungi reproduce?
Fungus reproduces by spore formation. Spore formation is a method of asexual reproduction. Spores are specialised structures that are resistant to sunlight and drying. Therefore, they can persist in the environment for many days or even months. These spores can germinate when the condition is favourable to produce a daughter fungus. You must have seen a powdery substance that sticks to all surfaces during the rainy season. The powdery substance is a fungus. During rains, the atmosphere is high in moisture. Therefore, this is a favourable time for fungal spores to germinate. The fungal spores that are present in the air settle on moist surfaces and then germinate, thus forming the powdery substance. The same principle is true for mushrooms as well.
Thus, the fungus is a ubiquitous organism that play a vital role in the natural world. The fungus has many important roles in medicine, everyday life and many commercial applications. Mycology is the study of fungus.
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