Kingdom Fungi (ch. 26)
If at first you don’t like a fungus …
Just wait a little, It will grow on you.

Mycology = study of fungi
General Characteristics of Fungi
Classification into Phyla / Divisions
based on Sexual Reproductive Structures
Effects on Humans – Diseases & Benefits
* You should know all examples *
General Characteristics of Fungi
• Heterotrophic saprophytes
(decomposers)  release / recycle
inorganic nutrients
• Reproduce mostly asexually
• Haplontic life style – grow from haploid
spores
• May also be parasitic, predatory, or form
other symbioses
General Characteristics of Fungi
• Secrete digestive enzymes onto food
 extracellular digestion 
absorption of nutrients
• Digestive enzymes can digest tough
substances, such as cellulose in wood
• Cell walls made of chitin, a
polysaccharide
• Multicellular, except for yeasts
(unicellular)
• Very efficient nutrient transport in
hyphae  grow very fast!
• Most are poisonous  leave it to the
experts to pick the fungus on your
plate…
Important Symbioses
Lichen = alga or cyanobacteria + fungus
–> soil formation from rock
Mycorrhyzae provide plant roots
w/ inorganic nutrients, receive sugars
Fungal Structure - Cells
• Hypha = multinucleated, filamentous cell
Fragmentation (asexual):
new fungus grows from fragment
↓
Septate hyphae
(septum = dividing wall)
Nuclei
Coenocytic hyphae
(no septa)
Nuclei
Cell walls made of chitin
Fungal Structure - Body
• Mycelium = network of hyphae  body of
fungus
Fruiting body
Mycelium
to disperse
of fungus on
spores
wood
Hyphae
Mycelium
“Fairy Rings” are mushrooms (fruiting bodies) that
grow at the tips of an underground mycelium:
Generalized Fungal Life Cycle
Haploid Spore Producing Structure:
Mitosis (n  n)
/Dikaryotic
Sporulation
n + n  2n
SPEED:
MAKE SPORES FAST!
RECOMBINATION:
GENETIC DIVERSITY
n
n
2n
Sporulation
Diploid Spore Producing Structure:
Meiosis (2n  n)
Basidiomycota
“Club Fungi”
Basidiomycetes ,
Ernst Haeckel,
1904
Sexual Reproduction
Dikaryotic Stage
Phylum
Basidiomycota
“Club” Fungi*
PLASMOGAMY
Secondary
KARYOGAMY
n + n  2n
mycelium
- mating type
+ mating type
Primary mycelium
Asexual
reproduction:
fragmentation of
septate hyphae and
asexual spores
Meiosis
*Basidium = Diploid Spore
Producing Structure:
Meiosis (2n  n)
Basidiospores
n
Rusts & Smuts Affect Plant Crops
Wheat stem rust - Puccinia graminis
Smut fungus on corn
Plylum Ascomycota - “Sac” fungi
(largest phylum)
Cup
fungi
Truffles
Includes Penicillium mold
Penicillium mold, an ascomycete
Phylum Ascomycota
Conidiophore = Haploid
Spore Producing
Structure:
Mitosis (n  n)
- mating type
+ mating type
Ascus = Diploid Spore
Producing Structure:
Meiosis (2n  n)
n + n  2n
n
Asexual Reproduction in Yeasts
(unicellular ascomycote)
Budding
YEAST
(MOTHER)
CELL
NEW YEAST CELL
Recent additions to Ascomycota…
Athlete’s food & Ringworm
Zygomycota
Ex.: black bread mold, Rhizopus stolonifer
(asexual)
Phylum Zygomycota
- mating
type
+ mating
type
Zygosporangium = Diploid
Spore Producing Structure:
Meiosis (2n  n)
n
2n
Sporangium = Haploid Spore
Producing Structure:
Mitosis (n  n)
(informal) Phylum Deuteromycota
• “Imperfect Fungi” because only observed to
reproduce asexually
May be moved to other phyla as research continues…
Predatory Fungus
Nematode-Trapping Fungus
Arthrobotrus , a deuteromycete,
capturing a round worm
(nematode)
Dimorphic Fungi
25 C 37 C
Can exist as
mold / hyphal / filamentous form
(usually at room temperature) or
yeast (body temperature) 
several potential pathogens:
Histoplasma capsulatum
Found in bat and bird feces
histoplasmosis; affects mainly
lungs, can disseminate through
body
Candida albicans
oral and genital infections
Benefits
• Medicines, including Penicillin, the first
antibiotic, isolated from Penicillium fungus
• Food: edible mushrooms, moldy cheese ,
fermentation products (wine, beer), leavened
bread (aerobic), etc.
• Biotechnology – yeasts used in research,
including cloning of genes
Fungal Foods
Yeast, sugar,
aerobic respiration
 CO2 makes
bread rise
Mold on blue cheese
Alcoholic fermentation (anaerobic)