The
fungal world: Basic
traits Slime
molds
(P)
These groups are not considered part of true fungi but are included
as they possess fungal-like qualities and are often mistaken in
identification...
First, all 3 groups are protista...
From the chart below you can see their walls are composed of cellulose although none are photosynthetic... mostly saprotropic or parasitic in nature.
Division Acrasiomycota no
flagellated stages ; fruiting body for asexual
spores Myxomycophyta flagellated
stages; coenocytic mass; phagocytosis Oomycota water molds,
white rusts, downy mildews; coenocytic hyphae; flagellated
life stages; oo = egg; water & soil #
Species 26 500 475 Wall cellulose cellulose cellulose gametes/
ploidy isogamy/haploid isogamy/diploid oogamy/diploid Example Dictyostelium Physarum Saprolegnia What is an
individual? the slime
you see on grass and shower curtains.. potato
blight, downy mildew, ick on fish
Dictyostelium is a cellular slime mold which normally lives as single amoeboid cells. Under stress ( lack of food & water, temperatures changes etc. ) amoebae will begin to secrete acarsin, a hormone-like substance which attracts other amoebae. They stream toward a center of aggregation cells and form a slug (pseudoplasmodium) . This slug can move but eventually stops and forms a stem with a spore-forming structure on top. The spores have thick walls made of cellulose & protein. After several divisions of the spore stage, the spores will give rise to amoebae.
In nature its is found in the soil or in dung feeding on bacteria.
As you can see from the chart above and through a comparison of the life cycles, there are many differences between the cellular and plasmodial slime molds... in the cellular slime molds the amoebae although they congregate don't lose their identity, while in the plasmodial, the mass is coencocytic.
You may have noticed these without realizing what are: if you see a slimy surface on your shower curtains or walls or a dewy layer on your lawn....
In the wilds below, growing on a plate above.....
