Kingdom Fungi Definition and Characteristics

Fungi are eukaryotic, usually multicellular creatures with a unique type of multicellularity. Because their cells are not completely separated by cell walls, cytoplasm and even nuclei can pass between them. Fungi are also responsible for the formation of black spots on bread that has been left outside for a few day. These are also found in the forms of mushrooms, and yeast cells, which are widely utilised in the manufacture of beer and bread. They are also present in the majority of skin infections and other fungal illnesses.

What is Fungi?

Microorganisms, including yeasts, mushrooms, and moulds, are fungi, which are eukaryotic organisms. These creatures are categorised as fungus in the kingdom Fungi. The creatures found in the Kingdom Fungi have a cell wall and are abundant. Among living creatures, they are classed as heterotrophs. The cell walls are made of chitin, a protein found in exoskeletons of arthropods that reflect fungi and Animalia's kingdoms close relationship. They are even more closely linked to one another than to plants. Fungi are classified as either parasite, which prey on plants, insects, and animals, or saprophytes, which primarily help in the decomposition of decaying organic matter.

Structure of Fungi

Fungi structure may be explained in the subsequent ways:

• With the exception of yeast cells, almost all fungi contain filamentous structures.
• They can be single-celled or multicellular in nature.
• Fungi are usually composed of thread-like structures known as hyphae. These hyphae create a mesh-like structure called mycelium.
• Fungi have a cell wall composed of chitin and carbohydrates.
• The cell wall is made up of protoplast, which differentiates into other cell components such as the cell membrane, cell organelles, cytoplasm, and nuclei.
• The nucleus is thick and transparent, with chromatin threads running through it. A nuclear membrane surrounds the nucleus.
• Easy to work on

Characteristics of Fungi

Fungi have the following key characteristics:

• Fungi are heterotrophic microorganisms that are eukaryotic, non-vascular, and non-motile.
• They might be unicellular or filamentous in nature.
• They proliferate by the use of spores.
• Fungi show the alternation of generation phenomena..
• Fungi do not have chlorophyll and so cannot undergo photosynthesis
• Fungi use starch to preserve their food.
• Chitin is created via biosynthesis by fungi.
• Fungi nuclei are very tiny.
• The fungus does not have an embryonic stage. Instead, they grow from the spores.
• Sexual or asexual reproduction both are used as the mode of reproduction.
• Some fungi are generally parasitic, which means they may infect the host.

Classification of Fungi

Kingdom Fungi are categorised according to their modes. Fungi are classified in the following ways:

Depending on the nutrition mode

The kingdom fungus may be divided into three categories based on nutrition.

1. Saprophytic fungi acquire their nourishment by feeding on dead organic matter. Rhizopus, Penicillium, and Aspergillus are a few examples.
2. Parasitic fungus gets their nourishment by living on other living creatures (plants or animals) and absorbing nutrients from them. Taphrina and Puccinia are two examples.
3. Symbiotic fungi are those that exist in an interdependent relationship with other species, benefiting both parties. Lichens and mycorrhiza are two examples.

Depending on the Spore Formation

Fungi are divided into the following kingdoms depending on the production of spores:
1. Zygomycetes -  are produced by the union of two distinct types of cells. The sexual spores are referred to as zygospores, whereas the asexual spores are referred to as sporangiospores. The hyphae lack septa.
2. Ascomycetes -  are also known as sac fungus. Coprophiles, decomposers, parasites, and saprophytes are all possible. Ascospores are sexual spores. Conidiospores are responsible for asexual reproduction. Saccharomyces cerevisiae is an example.
3. Basidiomycetes - The most prevalent basidiomycetes are mushrooms, which typically survive as parasites. Basidiospores are responsible for sexual reproduction. Conidia are used for asexual reproduction. Trichoderma is one example.

Reproduction in Fungi

Fungi reproduce in both sexual and asexual ways. The sexual mode of reproduction is known as teleomorph, while the asexual form of reproduction is known as an anamorph.
1. Budding, fission, and fragmentation are all methods of vegetative reproduction.
2. Asexual reproduction occurs by the use of spores known as zoospores, conidia, or sporangiospores.
3. Ascospores, basidiospores, and oospores reproduce sexually.
4. In the kingdom Fungi, the traditional manner of sexual reproduction is not always observed. For example, the union of two haploid hyphae does not result in the creation of a diploid cell in some fungi. In such situations, an intermediary stage known as the dikaryophase occurs.

Conclusion

If we look closely, we can see that all of the cases we listed include wet circumstances. As a result, we may conclude that fungi often flourish in damp, warm environments.