Fungi
By Jacob Squicciarini
and
Adryan Cheeseboro
Chapter Overview
What is a fungus?
What makes up a fungus?
Fungal evolution
Reproductive vocab
Types of fungus
Microsporidia
Chytrids
Zygospore fungi
Glomeromycota
Ascomycota
Basidiomycota
What is a Fungus?
A fungus is any organism that is part of the kingdom Fungi
which is separate from plants, animals, protists and bacteria.
• All fungi have chitin in their cell walls.
• Fungi survive by absorptive heterotrophy.
Saprobes – Absorb
nutrients from dead
organic matter.
Parasites – Absorb
nutrients from living
hosts.
Mutualists – live close
to or on living host in
a way that benefits
both organisms.
What makes up a Fungus?
Unicellular Fungi
o Unicellular fungi are known as yeasts.
o Yeasts live in moist environments and absorb nutrients directly across their
cell surfaces.
Multicellular Fungi
o The body of a fungus is called the mycelium.
o The mycelium is composed of individual tubular filaments called hyphae.
Nuclei
Septa
Septate
Coenocytic
Cell Wall
Fungal Evolution
Modern fungi are believed to have evolved from a
unicellular protist ancestor that had a flagellum.
Animals
Fungi
Plants
Unicellular protist
with flagellum
Important Reproductive
Vocab
Plasmogomy – The fusion of the cytoplasm of two
cells.
Karyogamy – The fusion of two nuclei from different
cells.
Spore – Unit of asexual reproduction.
Dikaryon – cell that contains two nuclei.
Mating Types – No male and female.
Types of Fungus
There are six major groups of fungus.
1.
2.
3.
4.
5.
6.
Microsporidia
Chytrids
Zygospore Fungi (Zygomycota)
Arbuscular Mycorrhizal (Glomeromycota)
Sac Fungi (Ascomycota)
Club Fungi (Basidiomycota)
Microsporidia
Characteristics
o
o
o
o
Unicellular (yeasts)
Among the smallest eukaryotes known
No mitochondria
Strictly intracellular parasites of animals
Reproduction
Chytrids
(Chytridiomycota, Neocallimastigomycota, and
Blastocladiomycota)
Characteristics
o Aquatic
o Only fungi with flagella at any life cycle stage
o Parasitic or saprobic
Reproduction
o Sexually or asexually
o Gametes have flagella
Zygospore Fungi
(Zgomycota)
Characteristics
o Saprobes, parasites of insects and spiders, or mutualists of other fungi and
invertebrate animals.
o Only one diploid cell (zygote) in entire life cycle.
o Coenocytic hyphae
Reproduction
Glomeromycota
common name: Arbuscular mycorrhizal fungi
a type of mycorrhiza in which
the fungus penetrates the
cortical cells of the roots of a
vascular plant.
REPRODUCION
The Glomeromycota have generally
coenocytic (occasionally sparsely septate)
mycelia and reproduce asexually through
blastic development of the hyphal tip to
produce spores.
Ascomycota
common name: Sac Fungi
Reproduction
 Asexual (1N)
-Haploid cloning by 2 processes
• Asexual – conidia
 Sexual
-Alternation between haploid
and short-lived diploid stages
• Sexual – Ascus
- Meiosis
-Produce 1N spores for sexual
reproduction
The products of meiosis in sac fungi are
borne in a microscopic sac called ascus.
The fleshy fruiting bodies consist of
both dikaryotic and haploid hyphae.
Basidiomycota
common name: Club fungi
Reproduction
•
•
•
•
•
Hyphae fuse to form
heterokaryotic mycelium
Mixed cytoplasm of haploid nuclei
Fusion of haploid nuclei into
diploid nucleus in basidium
Meiosis in basidium produces
haploid (1N) spores
Spores grow into hyphae
In club fungi, the products of meiosis are
borne exposed on pedestals called basidia.
Fruiting bodies consist solely of dikaryotic
hyphae, and the dikaryotic phasecan last a
long time.
Sources
http://www.anselm.edu/homepage/jpitocch/genbi1
01/diversity3_Fungi.html
http://faculty.clintoncc.suny.edu/faculty/michael.gre
gory/files/bio%20102/bio%20102%20lectures/fungi/fun
gi.htm#Phylum:%20Glomeromycota
http://bcs.whfreeman.com/thelifewire9e/default.asp
#542578__591454__