Fungi

zoospore

Flagellated spore.

ascocarp

Fruiting body of an ascomycete.

Summarize the current scientific understanding of fungal evolution.

Currently, scientists propose fungi evolved from single-celled flagellates, the same organisms animals evolved from. The surprising revelation is that fungi appear to be closer related to animals than they are to plants. Scientists have divided fungi into five main groups, based on all of the most relevant evidence and genetic analysis.

nucleariid

Nonfungal and nonanimal member of opisthokonts.

microsporidia

Single-celled fungi or closely related to fungi.

basidium

Dikaryotic structures on which basidiospores develop.

zygomycete

A member of a group of fungi that include some fruit and bread molds.

chytrid

A type of fungi that has symbiotic associations with herbivores; associated with amphibian deaths.

glomeromycete

A type of fungus that forms a mutualistic relationship with the roots of plants and trees; exists in some symbiotic relationship with 90% of the plant species on Earth.

basidiomycete

A type of fungus with a club-like shape that bears sexually produced spores on a basidum; member of the class Basidomyctes, a large group of fungi including puffballs, shelf fungi, rusts, smuts, and mushrooms.

opisthokonts

Clade of Eukaryotic flagellate-originating organisms.

basidiocarp

Club-like fruiting structure in basidiomycetes.

ascomycete

Cup fungi.

Describe the main characteristics of various forms of fungi, including specialized structures.

Each of the fungal groups can be characterized often by specialized structures all members share. Typically, these structures relate to asexual and sexual reproductive cycles or nutrition. Chytrids produce a unique motile spore known as a zoospore that can easily swim in either a thin layer of water between soil particles or in a pond full of water. All other fungi produce non-motile cells known as spores, reproductive units that are highly resistant to environmental extremes. Many Zygomycetes reproduce sexually by making zygospores from a zygosporangium, but they can also make spores when they reproduce asexually. Glomeromycetes are known to make unique chlamydospores and make hyphae that live primarily inside plant roots. Ascomycetes are known as sac fungi because when they reproduce sexually, the ascospores are made in a small sac-like structure. The sacs are borne on the surface of an ascocarp, a fruiting body. Ascomycetes can also reproduce asexually by making lots of spores called conidia. Basidiomycetes reproduce sexually by making basidiospores on the surface of a club-like structure known as a basidium. The microscopic basidia (plural for basidium) are found on the surface of a basidiomycete basidiocarp fruiting body often referred to as a mushroom.

zygosporangium

Structure produced during sexual reproduction of zygomycetes where karyogamy and meiosis occur.

conidia

Structures on which asexual spores are produced