Fungi
Chapter 31
• Fungi - heterotrophs - eat by
absorbing nutrients - by secreting
enzymes to outside which digest
food around them; fungi absorbs
food.
• Fungi composed of hyphae - make
up fungi’s mycelium (feeding
network)
• Fungi multicellular - hyphae divided
by septa.
• Septa have pores to allow transfer
of material from one to another.
• Parasitic fungi adapted to attack
host by burrowing into host with
haustoria.
• Fungi can reproduce sexually or
asexually.
• Spores produced and released from
parent fungi.
• Sexual reproduction - parent’s
cytoplasm fuse together
(plasmogamy).
• Haploid nuclei then fuse together
(karyogamy)
Diversity
• Phylum Chytridiomycota – chytrids aquatic fungi that can be parasitic.
• Cell walls made of chitin - most
primitive fungi; probably evolved
from protists that had flagella.
• Phylum Zygomycota –zygote fungi mostly terrestrial; can form
mutualistic relationships with plants
(mycorrhizae).
• Unfavorable conditions - can form
resistant spores to wait until
conditions are favorable before
germination.
• Phylum Ascomycota – sac fungi found everywhere.
• Most live in mutualistic relationship
with algae - lichen.
• Fungi keep sexual stage in fruiting
body - asocarp.
• Phylum Basidiomycota – club fungi mushrooms.
• Reproduce by fruiting bodies basidiocarps.
• Asexual reproduction very
uncommon.
Other types
• Molds fast growing, asexual fungi.
• Mold refers to early asexual stage
of fungus not classified into
phylum.
• Yeasts reproduce asexually - fungus
that inhabits water and is
unicellular.
• Lichen result of relationship
between algae and fungus.
• Alga gives fungus food; fungus gives
alga place to grow and protection.
• Mycorrhizae result of relationship
between plant roots and fungi.
• Help increase surface area for
absorption to take place.
Fungal impacts
• Fungi important to ecosystem - help
to break down inorganic nutrients
that plants can use.
• Percentage of fungi parasitic and
contribute to damaging crops and
various plant species.
• Can also cause skin infections in
humans.
• Fungi used for food (mushrooms,
cheeses), components of soda,
antibiotics, and in bread making and
brewing (yeasts).