Many fungus-like species, such as slime moulds and oomycetes (water moulds), do not belong to the kingdom Fungi yet are commonly referred to as fungi. Many of these fungus-like creatures belong to the Chromista kingdom. Fungi are among the most extensively dispersed creatures on the planet, and they play an important role in both the environment and medicine. Many fungi live free in the soil or water, while others have parasitic or symbiotic interactions with plants or animals.
Fungi are eukaryotic organisms that include yeasts, moulds, mushrooms, and various microorganisms, among others. The fungal kingdom is home to these species. The Kingdom Fungi’s organisms have a cell wall and are widely spread. They are classified as heterotrophs among living things.
Fungus is derived from the Latin word meaning mushroom. Many varieties of fungus employ the familiar mushroom as a reproductive structure. Many fungi species, on the other hand, do not produce mushrooms at all. A typical fungal cell has a genuine nucleus and several membrane-bound organelles, as it is a eukaryote. The Ascomycota, or real Fungi, are a diverse group of living creatures that belong to the kingdom Fungi. Scientists have detected roughly 100,000 fungal species, but this is a small proportion of the 1.5 million species that are likely to exist on the planet. The kingdom Fungi, which belongs to the domain Eukarya, includes edible mushrooms, yeasts, black mould, and Penicillium notatum, the creator of the antibiotic penicillin.
Characteristics of Fungi
- Thallus Organization: A thallus is the plant body of true fungus. It might be mycelial or non-mycelial. Non-mycelial forms are single-celled. Budding, on the other hand, may result in the formation of a pseudo mycelium. The plant body in mycelial forms is made up of thread-like structures called hyphae (sing. hypha).
- Cell Organisation: Chitin and cellulose make up the majority of fungi’s cell walls. Chitin is a N-acetylglucosamine polymer. On the other hand, cellulose is nothing more than a d-glucose polymer. Furthermore, cellulose-glycogen, cellulose-chitin, or polyglucosamine-galactan may be used to make the cell wall.
- Nutrition: The organisms are achlorophyllous fungus. As a result, they are unable to make their meals. They exist as parasites and saprophytes, respectively. Some green organisms coexist with other green forms in a symbiotic relationship.
- Parasites: They get their sustenance from a living host most of the time. It’s possible for a parasite to be either facultative or obligatory. Throughout their lives, obligatory parasites survive and settle on a living host. Saprophytes that have turned parasitic are known as facultative parasites.
- Saprophytes are organisms that get their food from dead or decaying organic waste. Saprophytes are classified as either obligatory or facultative. An obligatory saprophyte is a saprophyte for the rest of its existence. A facultative saprophyte, on the other hand, is nothing more than a parasite that has evolved into a saprophyte.
- Symbionts: Certain fungi form symbiotic relationships with green or blue-green algae. The lichen is made up of these. The algal component is photosynthetic in this case. The fungal component is in charge of reproduction.
- Reproduction: In fungus, sexual and asexual reproduction are both possible. The sexual mode of reproduction is called teleomorph, while the asexual way of reproduction is called anamorph.
- Fragmentation: Some Ascomycotina dan Basidiomycotina species reproduce by breaking the mycelium.
- Budding is a method of multiplication used by some one celled species. A bud begins as a papilla on the parent cell and then expands into a wholly different entity following expansion.
- Fission is a mechanism that allows a few one celled organisms, such as yeasts and slime moulds, to reproduce.
- Asexual reproduction is a type of reproduction that occurs without the need of
- Sporangiospores are non-motile, thin-walled spores that develop in sporangia. They might be uninucleate or multinucleate. They are also known as aplanospores because of their structure.
- Zoospores are motile, thin-walled spores that originate in a zoosporangium.
- Conidia: Spores are not generated inside a sporangium in certain fungi. They are born on the ends of conidiophores, which are unique branches. These spores are hence conidia.
- Sexual reproduction may be found in all families of fungus, with the exception of Deuteromycotina (Fungi imperfecti). The compatible nuclei exhibit a unique behavior during sexual reproduction, which is responsible for the commencement of three separate mycelial phases.
Structure of Fungi
- Except for yeast cells, almost all fungi have a filamentous structure.
- It might be a single-celled creature or a multicellular entity.
- Fungi have lengthy thread-like filaments called hyphae. Mycelium is a mesh-like structure formed by these hyphae.
- The cell wall of fungi is made up of chitin and polysaccharides.
- The cell wall is made up of protoplast, which is then differentiated into cell membrane, cytoplasm, cell organelles, and nuclei.
- The nucleus is thick, transparent, and threaded with chromatin. A nuclear membrane surrounds the nucleus.
Classification of Fungi
Phycomycetes: These can be found in watery situations as well as on decaying wood in moist and humid environments. The mycelium is coenocytic and aseptate. Asexual reproduction is accomplished by the use of zoospores (motile) or aplanospores (asexual) (non-motile).
Rhizopus/Mucor: They are global and saprophytic fungi that feed on decomposing organic materials. On wet bread, Rhizopus stolonifer is particularly common. As a result, they’re known as black bread moulds.
Albugo: It’s an obligatory parasite that lives in the intercellular gaps of the host’s tissues. It feeds on Cruciferae, Compositae, Amaranthaceae, and Convolvulaceae members. White rust or white blisters are the symptoms of this fungus’s infection. Albugo candida is the most well-known and common species. It kills mustard embers (Cruciferae).
Ascomycetes: They might be saprophytic, decomposers, parasitic, or coprophilous in nature (growing on dung). Aspergillus, Claviceps, and Neurospora are only a few examples of fungal pathogens. In biochemical and genetic research, Neurospora is frequently employed.
Yeast: In 1680, Antony Van Leeuwenhoek published the first description of yeast. Yeast is a non mycelial or unicellular organism that is very tiny and shaped spherically or oval. Although individual cells are colourless, colonies can be white, red, brown, creamy, or yellow in appearance. Yeast reproduces in a variety of ways, including vegetative, asexual, and sexual reproduction.
Basidiomycetes: Puffballs, mushrooms, and bracket fungus are the most prevalent basidiomycetes. Rusts and smuts, for example, grow in soil, on logs and tree stumps, and as parasites in living plant bodies. They have septate and branching mycelium. There are no sex organs in these creatures. Plasmogamy, on the other hand, occurs when two vegetative or somatic cells of different strains or genotypes fuse.
Uses of Fungi: Fungi are one of the most important groups of creatures on the planet, since they play a key part in the biosphere and have significant economic value due to both their beneficial and detrimental impacts.
- Fungi are used for a variety of purposes, including the following:
- They play an important part in the recycling of dead and degraded materials.
- Food – Mushroom species that have been produced and utilised as food by humans are edible.
- Medicines – Antibiotics are produced by a variety of fungi, which are used to treat illnesses in people and animals. Penicillin, obtained from the Penicillium fungus, was the first antibiotic to be mass-produced.
Examples of Fungi:
Fungi can be found in a variety of forms, as follows:
Hence it can be concluded by stating that They are significant in both grassland and forest habitats as decomposers and pathogens, and they play a key role in the food chain. Fungi have a wide range of relationships with other living and dead creatures.