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Chapter 24
Kingdom Fungi
Characteristics of Kingdom Fungi
Heterotrophic
 Store food as glycogen instead
of starch
 Most are saprobes- fungi that
feed on organic wastes and
remains. Some are parasites

Characteristics of Kingdom Fungi
Have cell walls. Walls made of chitin (like
insects) instead of cellulose (like plants
and protists)
 Fungi are classified based on
types of structures produced during sexual
reproduction.
 Largest groups: zygomycetes,
basidiomycetes, and ascomycetes

Extracellular Digestion
Fungi digest tissues by secreting digestive
enzymes onto the tissue. Then they
absorb the digested product.
 This is beneficial to plants and the fungi
 Mycelium- net of filaments (filament=
hyphae). Provides high surface area to
volume ratio for absorbing nutrients.

Zygomycetes
Terrestrial and mostly saprotrophs. Some
parasites
Highlighted genus: Rhizopus
R. stolonifer- black bread mold
Zygospores (2n) produce reproductive
spores (n)
Basidiomycetes- Club Fungi
Grocery store mushrooms
 Spores form in basidia- club shaped
structures that form from mycelia
 Basidia (n+n) produce zygotes

Ascomycetes- Sac Fungi
Spores form in sac-shaped asci cells.
 Baking yeast
 Aspergillus (citric acid), Penicillium
(cheese and antibiotics), food spoiling
fungi
 Largest group

The Unloved Species
READ SECTION 24.5 on pg. 397
 Be familiar with some common harmful
fungal species.

The Symbionts
Endophytic fungi live inside plants.
 The symbiotic relationship between fungus
and plant results in benefits for both
species.
 Lichens and fungus-roots

Lichens
Symbiotic relationship between a
photosynthetic species and a fungus.
 Photobiont- photosynthetic portion (ex:
cyanobacteria)
 Mycobiont- fungal portion- largest
component
 Live in places too hostile for other speciesfrozen rocks,

“Old Man’s Beard”- an indicator of
air pollution
Fungus-roots
Soil fungi that are mutualists with young
tree roots.
 “Micorrhiza”- the symbiotic network of
roots+ fungus
 Increases the absorptive surface area.
 Plant gives up some sugars. Fungus gives
up absorbed nutrients.

Mycorrhizae
Increases the absorptive surface area.
 Plant gives up some sugars. Fungus gives
up absorbed nutrients.
