How do zygomycetes differ from basidiomycetes

Look at the diagram below:. Ascomycota Basidiomycota. Basidiomycota and Ascomycota are more closely related to one another than either is to Zygomycota or Chytridiomycota.

Or you could say that all of the Basidiomycetes and Ascomycetes share a common ancester that is not shared with the other groups. The branches leading to Zygomycota and Chytridiomycota are dashed to show that there is more than one lineage in these groups.

The relationships within these two groups is not well understood. You can explore phylograms in more depth in the classification section. At the Tree of Life Web Project you can explore many branches of fungal phylogeny in more depth. Note than this is a work in progress, however. Scientists continue to get new data and revise and refine their hypotheses. The most modern classification science has confirmed that these are the four main groups of fungi.

Several other groups of life such as slime molds and certain multicellular bacteria that were once thought to be fungi are now excluded based on modern methods, and the chytridiomycota which had been removed from the fungi by the 5 kingdom system because they are motile move around , have now been confirmed to be members of the group.

Chytridiomycota chytrids pronounced kih-tridz TOLpage. About 1,, mostly aquatic species of Chytrids are known. They can be unicellular or filamentous , and can have motile zoospores which swim to new substrates. It is convenient to compile these simplest of fungi at the base of the fungus tree into one group, however, it is becoming clear that there multiple groups of Chytrids. Zygomycota zygomycetes pronounced zie-go-my-seats TOLpage.

Most of the about 1, known Zygomycetes are terrestrial. They are filamentous , but have no multicellular fruitbody. Instead, they form zygospores that are left behind in the soil where two compatible hyphae meet. The morphologically similar Glomeromycota , which are very important to rainforest ecology have been put in this group traditionally, however they represent a separate lineage that is closer to the Basidiomycota and Ascomycota. Ascomycota ascomycetes pronounced ask-oh-my-seats TOLpage.

Ascomycetes are named for the ascus, an 8-spored sac which is used for spore dispersal. Hence the common name, sac-fungi In this scanning electron micrograph the ascus coat is peeled away revealing 8 spores. Ascomycetes come in many shapes and sizes. Paecilimyces species fruiting from insect carcass, courtesy of P.

Ascomycetes can be filamentous or unicellular. Since they do not possess the sexual structures that are used to classify other fungi, they are less well described in comparison to other divisions.

Most members live on land, with a few aquatic exceptions. They form visible mycelia with a fuzzy appearance and are commonly known as mold. Molecular analysis shows that the closest group to the deuteromycetes is the ascomycetes. In fact, some species, such as Aspergillus , which were once classified as imperfect fungi, are now classified as ascomycetes. Example of an imperfect fungus : Aspergillus niger is an imperfect fungus commonly found as a food contaminant.

The spherical structure in this light micrograph is a conidiophore. Reproduction of Deuteromycota is strictly asexual, occuring mainly by production of asexual conidiospores. Some hyphae may recombine and form heterokaryotic hyphae. Genetic recombination is known to take place between the different nuclei.

Imperfect fungi have a large impact on everyday human life. The food industry relies on them for ripening some cheeses. The blue veins in Roquefort cheese and the white crust on Camembert are the result of fungal growth. The antibiotic penicillin was originally discovered on an overgrown Petri plate on which a colony of Penicillium fungi killed the bacterial growth surrounding it.

Many imperfect fungi cause serious diseases, either directly as parasites which infect both plants and humans , or as producers of potent toxic compounds, as seen in the aflatoxins released by fungi of the genus Aspergillus.

Glomeromycetes are an important group of fungi that live in close symbiotic association with the roots of trees and plants.

In the kingdom Fungi, the Glomeromycota is a newly-established phylum comprised of about species that live in close association with the roots of trees and plants. Fossil records indicate that trees and their root symbionts share a long evolutionary history. It appears that most members of this family form arbuscular mycorrhizae: the hyphae interact with the root cells forming a mutually-beneficial association where the plants supply the carbon source and energy in the form of carbohydrates to the fungus while the fungus supplies essential minerals from the soil to the plant.

This association is termed biotrophic. The Glomeromycota species that have arbuscular mycorrhizal are terrestrial and widely distributed in soils worldwide where they form symbioses with the roots of the majority of plant species.

They can also be found in wetlands, including salt-marshes, and are associated with epiphytic plants. Glyomeromycetes and tree roots : This image illustrates the bitrophic relationship between a glomeromycota Gigaspora margarita and the roots of a plant Lotus corniculatus.

The glomeromycetes do not reproduce sexually and cannot survive without the presence of plant roots. They have coenocytic hyphae and reproduce asexually, producing glomerospores. The biochemical and genetic characterization of the Glomeromycota has been hindered by their biotrophic nature, which impedes laboratory culturing.

This obstacle was eventually surpassed with the use of root cultures. With the advent of molecular techniques, such as gene sequencing, the phylogenetic classification of Glomeromycota has become clearer. This gene is highly conserved and commonly used in phylogenetic studies so it was isolated from spores of each taxonomic group. Using a molecular clock approach based on the substitution rates of SSU sequences, scientists were able to estimate the time of divergence of the fungi.

This analysis shows that all glomeromycetes probably descended from a common ancestor and million years ago, making them a monophyletic lineage. A long-held theory is that Glomeromycota were instrumental in the colonization of land by plants. Privacy Policy. Skip to main content. Search for:. Classifications of Fungi. Chytridiomycota: The Chytrids Chytrids are the most primitive group of fungi and the only group that possess gametes with flagella.

Learning Objectives Describe the ecology and reproduction of chytrids. Key Takeaways Key Points The first recognizable chytrids appeared more than million years ago during the late pre-Cambrian period. Like protists, chytrids usually live in aquatic environments, but some species live on land. Some chytrids are saprobes while others are parasites that may be harmful to amphibians and other animals. Chytrids reproduce both sexually and asexually, which leads to the production of zoospores.

Chytrids have chitin in their cell walls; one unique group also has cellulose along with chitin. Chytrids are mostly unicellular, but multicellular organisms do exist. Key Terms chytridiomycete : an organism of the phylum Chytridiomycota zoospore : an asexual spore of some algae and fungi flagellum : a flagellum is a lash-like appendage that protrudes from the cell body of certain prokaryotic and eukaryotic cells coenocytic : a multinucleate cell that can result from multiple nuclear divisions without their accompanying cytokinesis.

Zygomycota: The Conjugated Fungi Zygomycota, a small group in the fungi kingdom, can reproduce asexually or sexually, in a process called conjugation. Learning Objectives Describe the ecology and reproduction of Zygomycetes. Key Takeaways Key Points Most zygomycota are saprobes, while a few species are parasites. Zygomycota usually reproduce asexually by producing sporangiospores.

Zygomycota reproduce sexually when environmental conditions become unfavorable. To reproduce sexually, two opposing mating strains must fuse or conjugate, thereby, sharing genetic content and creating zygospores. The resulting diploid zygospores remain dormant and protected by thick coats until environmental conditions have improved. When conditions become favorable, zygospores undergo meiosis to produce haploid spores, which will eventually grow into a new organism. Key Terms zygomycete : an organism of the phylum Zygomycota karyogamy : the fusion of two nuclei within a cell zygospore : a spore formed by the union of several zoospores conjugation : the temporary fusion of organisms, especially as part of sexual reproduction.

Ascomycota: The Sac Fungi Most fungi belong to the Phylum Ascomycota, which uniquely forms of an ascus, a sac-like structure that contains haploid ascospores.

For example, the zoospore pattern of Saprolegnia is said to be dimorphic, as is the life style of Mucor rouxi i. What does dimorphic mean in general, and how does it apply to M. Why did he do that? Rhizopus stolonifer and Pilobolus crystallinus are both extremely successful at dispersing their asexual spores, yet you will find R. Explain how their dispersal methods differ and why their ranges differ.