Intro Flashcards
Are fungi auto or heterotrophic?
heterotrophic
What organelle do fungi lack that make them incapable of being autotrophs?
chlorophyll
T or F: fungi have both a cell membrane and a cell wall
true
What are fungal cell walls mostly made of?
chitin
What are the multicellular filaments that define many fungal forms called?
hyphae
What is the defining feature of most fungi?
hyphae
What are growth forms other than hyphae (mycelium) that fungi can have?
single-celled/yeast-like
T or F: fungi are motile
false! except for some germ cells
How do fungi digest organic substrates from their environment?
they release enzymes
What are 6 major fungal lifestyles?
pathogens
saprobes
parasites
endophytes
epiphytes
symbionts
What are pathogens? Give fungal examples
An organism that infects a host and causes a disease in the host
Describe saprobes. Give fungal examples
a group of fungi that decompose organic matter (feed on decaying wood, leaves, leaf litter)
Describe parasites. Give fungal examples
a group of fungi that live on or in a host
What is the difference between a pathogen and parasite?
pathogens infect hosts and cause disease
parasites live on or in a host
What is an endophyte? Give fungal examples
a group of fungi that colonize in living plant tissues
endosymbionts
What are epiphytes? Give fungal examples
fungi that grow on the external surface of plants
ex. black mildews
What are symbionts? Give 2 fungal examples
an association between organisms of different species
ex.
mycorrhizal fungi and trees
lichen (multiple fungi + algae)
T or F: fungi have pretty universal lifestyles amongst the different phyla
false, they have highly variable lifestyles (ex. saprobes, endophytes, epiphytes, etc)
T or F: fungi are highly successful
true
Where are fungi found (distribution)?
terrestrial and aquatic ecosystems
What are 3 characteristics of fungi that make them so successful?
- they can inhabit (are adapted to) both terrestrial and aquatic systems
- they can exploit a wide range of hosts and carbon substrates
- they reproduce and disperse by spores and can have very many
How many accepted species of fungi are there currently?
~120,000
(~8%)
What is the minimal estimate of fungal species?
~1.5 million
T or F: defining fungal species is easy
false
Are Oomycetes fungi?
NO, they are very similar but are in a totally different branch of life
What are 2 examples of Oomycete plant pathogens with effects on plants that are relevant to humans?
Phytophthora ramorum causes sudden oak death
Plasmopora viticola causes downy mildew
What are 2 examples of true fungal plant pathogens with effects on plants that are relevant to humans?
Puccinia graminis causes wheat rust
Ustilago maydis causes corn smut
What is an example of an opportunistic human pathogen?
Candida albicans causes Thrush
Describe Candida albicans and the disease (Thrush) it can cause
a dimorphic fungi that is an opportunistic pathogen (commensalism = benefit to fungus but no harm/benefit to host)
often there’s no negative effect in healthy humans, but if human has a weakened immune system = thrush
very common
can infect skin, fingernails, digestive tract, internal viscera, organs
treated with fungistatic drugs
Describe Cryptococcosis neoformans var. gatti and the disease it can cause in humans/mammals
It is a fungal pathogen of humans/mammals that can cause a pulmonary (lung) infection
it is dimorphic
recently introduced to BC and PNW
What does dimorphic mean?
a single species has 2 different morphologies
could be life stage related
How are fungi related to human allergies?
fungal spores are a major allergen
10,000-20,000 spores per m^3 of air exist and can cause adverse effects
What group of people are most exposed to fungal spore allergens?
agricultural workers
What causes the musty odor smell?
volatile secondary metabolites that fungi can produce (including aldehydes and ketones)
What are 2 examples of fungal allergens?
Alternaria alternata
Cladosporium sphaerosporum
In what ways can fungi have an economic impact?
fungi that function as plant pathogens can reduce agricultural yields and degrade stored crops
saprobes degrade timber, textiles, leather, paint, glue, plastics, chemical, petroleum, optical glass (anything carbon-based)
What 2 ways do fungi benefit ecosystems?
- essential to nutrient cycling in soils because they can degrade cellulose and lignin (no other organism can degrade lignin)
- mycorrhizal fungi promote plant growth and agricultural crop growth
How are fungi important to the human food sector?
mushrooms as a food source,
yeast for fermentation products
How does the industrial sector benefit from fungi?
- antibiotics (penicillin, cephalosporin)
- immunosuppressants (cyclosporin has been major for organ transplant success)
- used as model organisms for biotechnology and genetic research
- used in biopharmaceuticals
What are considered fungi?
yeasts, microfungi, mushrooms, mycelia
What is the difference between hyphae and mycelium?
A hypha (s.) is the individual filament and a group of hyphae (pl.) make up a mycelium (s.) which is the filamentous growth form of fungi
