FungiBy: Dominic DeCarlo, Brett Rosato, and Brendan Beecher

Chapter: 30

Outline

- What is fungus?- How do fungi interact with other

organisms?- What variations exist among fungal

life cycles?- How have fungi evolved and

diversified?

What is fungi? 30.1Fungus originally evolved

from a uni-cellular protist ancestor that had a flagellum.

Types:1. Saprobes2. Parasites

3. Mutualists

6 major classifications:1. Microporidia Fungi

2. Chytrids Fungi3. Zygospore Fungi4. Arbuscular mycorrhizal

fungi5. Sac Fungi 6. Club Fungi

Fungus reproduction 30.1

Fungus reproduce sexually and asexually.

Asexual reproduction takes many forms:- The production of haploid

spore within structures called sporangia

- Cell division by unicellular fungi; a equal division between one cell into two (fission) or any asymmetrical division in which a smaller daughter cell is produced (budding)

- Simple breakage of the mycelium

Fungi sexual reproduction:- There is no constant

distinguisher between a male and a female Fungus, it is a genetic determination between two or more mating types. If two mushrooms have the same mating type they can mate; the mushrooms have to have 2 different mating types within the same species to avoid self-fertilization.

- They reproduce sexually when the hyphae of different mating types meet and fuse.

How do Fungi interact with other organisms 30.2

Without fungi on our Earth you can imagine a very bare land with lots of watery environment's with dead organisms covering the ground. Many of the organism that are out their wouldn’t be around if the fungus didn’t feed off it/ with it.

Saprobic Fungi:- Are a major part to the earths carbon cycle, like other bacteria these fungi feed off of dead organic matter. If the fungi never feed off the dead organic matter, like tree leaves, bark, etc. there would be an extreme excess of carbon atoms would remain on Earth when instead the Fungus converts it into CO2 then released into the environment.

Parasitic Fungi:- Feed off of the life of a other organism.There are Facultative -- Fungi which attack living organism for benefit but can also grow on their own.- There are Obligate Fungi that can only grow off a specific host; usually a plant. They have a specialized nutrient requirement since they live primarily off a living host.

Mutualist Fungi:- Certain kinds of relationships between Fungi and other organisms have nutritional consequences for both sides.- There is a symbiotic relationship; which is when the two organisms are permanently together and in contact with one another- Then there is a mutualistic relationship which is when both organism benefit. - lichens: a fungus and photosynthetic organism can live off each other forever in the harshest environment's

Fungi life cycles 30.3

Different fungal groups have different life styles. Alternation of generations can occur within some Chytrids. This is the only group with flagella.

- The alternation occurs between haploids and diploids. The alternation is not typical amongst other fungal groups.

Sac fungi and club fungi go through a unique stage called a dikaryon.

- The products of reproduction in the sac fungi are contained in fruiting bodies of dikaryotic and haploid hyphae.

-Club fungi are different. The products of meiosis in these fungi are exposed on pedestals called basidia. They are only made up of the dikaryotic hyphae, and the dikaryotic phase lasts much longer than sac fungi.

The sporangium of zygospore fungi contain haploid nuclei that are included in the spore.

How have Fungi evolved and diversified 30.4Evolution: the ancestor of all

fungi was thought to be aquatic like the chytrids, but fungi have changed to become key components of terrestrial ecosystems.

Fungus have no diversified into 5 different but genetically similar strains.

1. Microsporidia: are unicellular fungi with walls that contain chitin

2. Chytrids: include several distinct lineages of aquatic microorganisms once classifies with the protists

3. Zygomycota: include three major lineages; parasite, mutualistic, and terrestrial saprobes

4. Ascomycota: Are terrestrial fungi that associate with plant roots in a close symbiotic relationship

5. Basidiomycota: otherwise known as club fungi

Sources

• Life the science of biology• http://en.wikipedia.org/wiki/File

:Fuzzy_Fungi_(Schizophyllum_commune).jpg

• http://pradhuman.com.np/lifecycle.html

• http://www.petinsurancecomparison.org/dog-health/fatal-fungi-mushrooms-that-can-be-harmful-to-pets/