In this post, learn all about classification of Fungi, their uses, advantages and disadvantages in detail.
What are Fungi?
Fungi are heterogeneous organisms coming together from three different kingdoms of life. However, these are positioned closer to animal Kingdom than to Plantae. The Fungi group generally includes yeasts, molds, and familiar mushrooms.
It is ranked as the Kingdom, and the higher classification of fungi is Eukaryotic. Now here, another question arises that what is the distinct similarity between plants and fungi? The answer, in the most straightforward way, is that both have cell walls in them.
Structure of fungi
Most fungi grow as thread-like filaments rather than single cells. Those filaments are termed hyphae (a plural term of hypha).
Each hypha constitutes one or more than one cell surrounded by a tubular cell wall. The bulk mass of hyphae makes up the body of the fungus, which is called mycelium (a plural term of which is mycelia).
Parts of fungus body
Fungi are free-living organisms surviving in soil or water. There some of them live in symbiotic relationships with plants and animals. Fungi are the most significant number of living organisms living on the planet Earth. There are three essential parts of fungi, all of them are described below:
- Fruiting body
It is a reproductive structure of fungi. A typical example of a fungal fruiting body is mushrooms. It is attached to the mycelium under the basic body structure. Moreover, a fruiting body always produces spores.
These are the fundamental parts that are involved in fungal reproduction. Fungal spores are haploid, which means they carry only one chromosome for each gene. Furthermore, they are quickly germinated when they strike damp soil.
The mycelium obtains nutrients and produces the fruiting body. Moreover, according to an estimation, the mycelium of one humongous fungus growing in Oregon covers more than 2,200 acres of tree forests.
What is Mycology?
Mycology is a branch of microbiology and is defined as:
The study of Fungi, their classification and the diseases associated with Fungi is called Mycology.
The biologist who work and study the fungi is called mycologist.
All properties about its cell construction, decaying, and processes are studied in this branch.
Characteristics of Fungi
Some of the general properties of Fungi are:
- All fungi are Eukaryotic and Classification of Fungi occurs in a distinct kingdom.
- They may be either unicellular (yeasts) or multicellular (molds)
- Naturally, they obtain their nutrients from a chemical in nature.
- They are primarily termed chemotrophic organisms.
- The natural habitats of fungi include water, soil, and decaying organic debris.
- Chitin and polysaccharides are primary constituents of the cell walls of fungi.
- Their reproduction is carried out both sexually and asexually.
- Paired chromosomes are unique, having true nuclei with the nuclear membrane.
- Non-motile cells show various degrees of specialization.
- Fungi grow as branching filaments called Hyphae.
Classification of Fungi
For every class distinction and category discrimination, there exists a solid basis to divide them. Fungi are classified on several different bases. Like they may either be classified based on their morphology, reproduction mean, or characteristic nature. Moreover, sometimes it may also be divided systemically based on several other environmental factors.
So, let’s see the classification of Fungi in detail:
Morphological Classification of Fungi
Depending on cell morphology, Fungi are classified into four significant groups. All of them are explained with complete details:
A unicellular fungus has a single nucleus.
They sexually reproduce by two means.
by actual spore formation sexually
While asexually by budding. Every bud can grow separately into new yeast.
These are seen as oval-shaped in microscopic view, having 3-15 microns diameter processing in tissues.
- Yeast like fungi
Budding or fission reproduce this unicellular fungus.
It looks like a spherical or oval structure having chains of elongated budding cells.
Microscopically, these fungi represent a network of end-to-end linked structures (pseudohyphae) in tissue formation.
Candida albicans are the best example of such yeast-like fungi
These are composed of hyphae as these multicellular fungi are reproduced by asexual means. Cottony and wooly appearance is viewed when they are seen under an electron microscope.
Molds are a combination of several hyphae with cross-walls that may have septa in them.
Moreover, some of them may lack such coenocytic property.
Usually, these are seen in tissues as thread-like filamentous hyphae.
Penicillium notatum is a perfect representation of such molds
- Dimorphic fungi
Yeast to molds converting ability having fungi is so-called Y M shifters. These have two forms that may cause disease in human bodies.
These fungi grow as a mycelial form in the soil at a variant temperature ranging 22-25oC. In response to environmental factors, they change their forms from yeast to molds.
Typically, these fungi are stable at 37oC.
Blastomyces dermatitidis are an excellent example of such dimorphic fungi
Systemic Classification of Fungi
Sexual spore formation is the basis of such a classification. These are placed in the phylum thallophyta. Four classes of such fungi are discussed below in detail:
Approximately 600 species are present in this class.
These fungi produce asexual spores called Sporangiospores that are held in swollen sac-like structures.
When the external environment is too harsh for fungus growth, their tough thick-walled zygotes remain dormant to keep them safe and protected.
Usually, asexual reproduction is seen in them, but as soon as the favorable conditions come back, it begins sexual reproduction again.
The common name of ascomycetes is ‘sac fungi.’
This group is having approximately 35,000 species compiled in them.
A common name for such fungi as sac fungi.
The fungi classified in this group usually contain septate hyphae and form exogenous spores called conidia.
Moreover, ascomycetes include yeasts and filamentous fungus, as many yeasts specifically are classified in this region because of sexual reproduction features.
These play a beneficial role, such as yeasts are used every day in baking, brewing, and wine fermentation.
Last but not least, they produce poisonous metabolites that somehow destroy crops.
Due to 30,000 different natural species of Fungi, these are termed as ‘club fungi.’
This class contains a club of several different kinds of fungi.
Sexual spores called basidiospores are formed on a basidium or base.
Smuts, jelly fungi, mushrooms, and bird net fungi are some of the most common Basidiomycota fungi examples.
Many mushrooms of this class are used as food in different countries of the world.
Besides all, this group contains shelf fungus, which is present at the bark of trees like small shelves.
Also, some important plant pathogens like smuts and rusts are present in this group.
The types of Fungi placed under the umbrella of this group are somehow said to be ‘imperfect fungi.’
This class has roughly more than 30,000+ species in them.
Most fungi present in this class usually reproduce using Conidia.
Only a few fungi are reported from freshwater and marine habitats; deuteromycete is one of them.
Ringworm is one of the most common diseases caused by such imperfect fungi.
Reproduction of deuteromycete is strictly asexual, so sometimes, hyphae may recombine and become heterokaryotic.
Pathological Classification of Fungi
In this type of classification strategy, all infected different plants, animals, and even human beings disease-causing fungi are separated from the beneficial ones. According to a rough estimation, almost 300 different fungi are known to be pathogenic to humans. Now let’s discuss them in detail:
- Primarily pathogenic
Those fungi that can become a source of many infections in healthy individuals are termed primarily as pathogens.
Such pathogenic fungi may cause disease of ‘Mycoses.’ These fungal infections in human can be classified according to tissues involved in
- Superficial Mycoses
- Visceral Mycoses (sometimes termed as systemic mycoses)
- Subcutaneous Mycoses
Cryptococcus neoformans are the most critical pathogenic yeast.
- Opportunistic pathogens
Those fungi attack infected patients who are immune-compromised.
They may also affect the individuals who are taking any immunity drugs
Moreover, these pathogenic fungi are dangerous and may cause the following different ailments:
Pathogenic fungi cause this disease due to toxic metabolic products like aflatoxicosis.
In addition to that, it may also be caused due to the consumption of aflatoxins grains. Those grains are commonly secreted by aspergillus flavus
This flavus resides in groundnuts, corn, and peas as there is no tissue invasion through such fungus.
Moreover, fungus of this class does not necessarily have to be present in tissues to exert its pathogenic effect since its toxic metabolites are always present there to some extent.
These are allergic reactions caused by the inhalation of fungal spores.
Examples include allergic bronchopulmonary and allergic fungal rhinosinusitis.
Unlike other fungi, these are not a single organism but instead present a symbiotic association between a fungus and an alga.
The primary role of Fungi
Fungi play their role as decomposers and recyclers. These are very helpful in maintaining a balance of the ecosystem. These fungi make it possible for other kingdom members to be supplied with nutrients that they require to live.
Humans have been indirectly aware of such blessing since it was impossible to turn the first tub of grapes into wine and bake a loaf of leavened bread. However, later people came to know the effects of fungi in many fields, including agriculture.
The best thing about Fungi is that they are responsible for breaking down organic matter and releasing carbon, oxygen, nitrogen, and phosphorus into the soil and atmosphere. That is essential for maintaining life on the planet Earth. Also, they are significant because they constitute an essential element in the sourcing of food.
Uses of fungi
Fungi serve us in several ways. Some of them are listed below:
- Yeasts produces vitamin B, which is of great use
- Like bacteria, fungi are also good decomposers
- Penicillin that is an essential antibiotic is obtained from the fungus
- Fungi are used in making bread in bakeries
- Fungi themselves serve as an essential source of food
Advantages of Fungi
The benefits of Classification of Fungi and mushrooms in the current environment are vast-ranging. It not helps the decaying process of dead plants and animals quickly but is also essential for processing dead material.
Some of the significant benefits of fungi are
- Most of the plant varieties require fungi for their speedy growth
- It fastens the decay process of dead animals and plants
- Most of the baking procedures are incomplete without the assistance of fungi
- In the pharmaceutical industry, several different kinds of fungi are utilized in making regular medicines.
- Moreover, fungi are essential for human civilizations and the rise of life on Earth
- Some fungi also provide us protein and vitamins necessary for cooking healthy food
- Several antibiotics are accessible from fungal species
- In the agricultural industry, it helps in making the soil fertile
Disadvantages of fungi
Despite so many benefits obtained from fungi, they also have some disadvantages. First of all, its excessive use can harm humans and plants as both can bear their intensity up to a specific limit.
A few disadvantages of fungi are
- It may cause several different kinds of human diseases like skin infections or cancers
- Fungi disturb agricultural growth on the ground level
- Sometimes, it becomes a hurdle in the production of enzymes and organic acids
- Some fungi, notable yeasts, do not form a mycelium or group
- Fungi disturb the cell walls of different plants with adverse effects of fungi, and they may rot
- Destroying timber may cause a significant loss of trees of any forest
- They cause economic losses if crops are affected by fungi causing plant diseases
Let’s explore some interesting facts about fungi
- Fungi can be both a reason for a disease or utilized in the production of different medicines.
- Its survival time is vast, so it lasts for a long time
- Mycologists classify fungi in several different ways
- Fungi can be deadly for several living organisms
- Fungi are the best solution for controlling pests
- It is the most significant number of living organism on the planet
- These organisms are vital to the environment