Fungi Flashcards
L 5, 6, 7 (140 cards)
1
Q
fungi are ___ heterotrophs
A
sessile
2
Q
why are fungi important
A
decomposers
expel CO2 in air for plants
helps dead plant release Carbon in soil
3
Q
what can fungi be
A
pathogens, predators
4
Q
how are fungi helpful
A
Required for carbon cycle (decomposition)
Make good food and beverages
Source of many antibiotics
Basic genetic research
Form important symbiotic
relationships
5
Q
how are fungi bad
A
Decompose things we don’t want them to (our food, fenceposts, etc)
Some produce mycotoxins
May attack living or dead organisms in temperatures ranging from -6° to 60° C
May cause disease in plants or
animals
6
Q
6 major groups of fungi
A
microsporidia, chytrids, sygomycetes, glomeromycota, ascomycota, basidomycota
7
Q
what fungi are zoosporic
A
microsporidiam, chytrids, sygomycetes, glomeromycota
8
Q
what fungi are dikarya
A
ascomycota, basidomycota
9
Q
Most fungi are ___, and the filaments are called
A
filamentous, hyphae
10
Q
Hyphae may form masses of filaments called a ___ (in nature these are generally underground), which give rise to the above ground ___ where ___ reproduction occurs
A
mycelium, fruiting bodies, sexual
11
Q
septate fungi
A
Some fungal hyphae are divided by walls called septa
12
Q
aseptate/coenocytic
A
Other fungal hyphae lack septa
13
Q
Not all fungi are filamentous – those that are not are generally referred to as
A
yeasts
14
Q
yeasts ranging from ___, ___, ___
A
zygomycetes, Ascomycota, and Basidiomycota
15
Q
Some fungi are even ___, and shift between ___ and ___ morphology
depending on the environment
A
dimorphic, hyphal, yeast
16
Q
All are heterotrophic absorbers, some even form specialized hyphae called ___
A
haustoria
17
Q
haustoria
A
to directly absorb nutrients from other organisms
18
Q
who does haustoria
A
either saprotrophs, parasites, or mutualistic symbionts
19
Q
single celled fungi
A
yeasts
20
Q
multicellular hyphae
A
coenocytic = aseptate or septet
21
Q
Fungi reproduce by forming
A
spores
22
Q
spores
A
unicellular haploid structures that can form another organism without the fusion of another cell
23
Q
are spores produced asexually or sexually
A
spores can be produced asexually or sexually
24
Q
asexual reproduction – spores are produced by ___ in ___ or from specialized hyphae form ___, or sometimes by ___ of hyphae
A
mitosis, sporangia, conidia, fragmentation
25
Sexual reproduction consists of three distinct phases:
* Plasmogamy
* Karyogamy
* Meiosis
26
what is plasmogamy
the fusion of two gametes
27
what is Karyogamy
the fusion of two nuclei (sometimes doesn’t happen for awhile, leading to dikaryotic cells – i.e. cells with two distinct nuclei)
28
meiosis in fungi
production of spores that restore the haploid state – specifically an example of zygotic meiosis
29
Budding in S. cerevisiae is an example of ___ reproduction
asexual
30
Sexual reproduction results in spores formed by meiosis in specialized structures – these are ___ with 8 ___
asci; ascospores
31
Cell division in conidia/conidiophores of Penicillium are an example of ____ reproduction
asexual
32
zygotes are ___, spores and gametes are ___, and meiosis always starts with a ___ cell forming a ___ cell!
diploid, haploid, 2n, 1n
33
describe microsporidia
monophyletic, unicellular parasites of animals, microsporidiosis
34
describe chytrids
monophyletic, coenocytic with motile spores and gametes, parasitic or saprophytic, mostly aquatic
35
Zoospores are motile spores that use a ___ for locomotion in an aqueous environment
flagellum
36
Zygomycetes are a ___ group of
filamentous fungi (~___ species)
polyphyletic, 1000
37
The first fungal group that conquered life on land
Zygomycetes
38
Zygomycetes live on ___ or are ___
decaying plant and animal matter, parasitic
39
what type of hyphae do Zygomycetes have
Coenocytic
40
how do zygomycetes asexually reproduce
Reproduce asexually by sporangia produced by hyphae
41
how do zygomycetes sexually
reproduce sexually by zygosporangia and form resting spores called zygospores
42
common type of zygomycetes
common bread mold - rhizopus
43
Sporangia is a term that refers to
a place where spores are made, can be asexual OR sexual
44
Reproduction in rhizopus is asexual... how?
asexual - spores produced in sporangia
45
Reproduction in rhizopus is sexual... how?
Sexual reproduction requires distinct mating types, + and - = heterothallic (vs. homothallic)
1) Gametangia (n) are produced via conjugation
2) Plasmogamy occurs: two cells fuse (fertilization)
3) Karyogamy occurs in the zygosporangia: + and – nuclei fuse forming the zygospore (2n)
4) Meiosis occurs during germination 2n → 1n
46
describe glomeromycota
All known species grow in association with plant roots, forming mycorrhizae = fungus root
Reproduce asexually
Found in association with ~80% of vascular plant species
~200 species
47
what are dikarya
Dikarya fungi have a prolonged life cycle stage with two distinct nuclei
2/3 of fungal species
not all are multicellular
48
dikaryotic fungi Plasmogamy
the fusion of two gametes, leading to dikaryotic cells – i.e. cells with two distinct nuclei)
49
dikaryotic fungi karyogamy
the fusion of two nuclei (sometimes doesn’t happen for awhile)
50
dikaryotic fungi Meiosis
production of spores that restore the haploid state – specifically an example of zygotic meiosis
51
asexual reproduction in ascomycota
more common
52
sexual reproduction in ascomycota
Sexual reproduction involves formation of an ascus (zygote) (2n)– a sac-like structure where karyogamy and meiosis occur to produce 8 ascospores (n) within
then females do ascogonium - female gemtangia (n)
then makes of antheridium - male gametangia (n)
the plasmogamy -> eukaryotic hyphae (n+n)
53
Ascus formation occurs on an ___
ascoma or ascocarp
54
what is the ascoma/ascocarp
the fruiting body, on an inner surface called the hymenium
55
Asci mature on the ___ of an ascomycete’s fruiting body/ascocarp
hymenium
56
Cup shaped fruiting body
apothecium
57
Asci and ascospores – ascoma may become ___ and ___ at maturity – aiding in ___ dispersal
turgid, rupture, spore
58
sac fungi
look likes sacs
59
asexual ascomycetes
penicillium, aspergillus, conidia, ringworm, athlete's foot
60
asexual reproduction in basidiomycota
rare
61
sexual reproduction in basidiomycota
Sexual reproduction involves formation of a
basidium – a club-shaped structure has eukaryotic mycelium (n+n), where karyogamy makes young basidium (2n) and then meiosis occurs to produce basidiospores on the surface to produce 4 spores/basidium (n).
then plasmogamy - (n+N)
now we have dikaryotic secondary mycelium (n+N)
62
Basidia formation occurs on a ___
basidioma or basidiocarp
63
what is basidioma or basidiocarp
the fruiting body, on a surface called the hymenium
64
The subphylum Agaricomycotina of basidiomycota has ‘___’ shaped fruiting bodies
mushroom
65
___ are formed by basidiomycota
fairy rings
66
do all basidiomycota form fruiting bodies?
no
67
which basiodiomycota do not form fruiting bodies
Subphylum Puccinio mycotina include rusts; Subphylum Ustilagino mycotina include smuts – both are plant pathogens
68
what is special about wheat rust?
it is heteroecious - requires two hosts
69
How have fungi evolved to efficiently disperse their spores?
Fungi have evolved diverse and efficient spore dispersal strategies to maximize survival and colonization. These include:
Wind Dispersal – Many fungi, like mushrooms and molds, produce lightweight spores that are released into the air and carried by wind.
Water Dispersal – Some aquatic fungi rely on water currents to spread their spores.
Animal Dispersal – Fungi like truffles attract animals that consume and spread spores through feces.
Explosive Mechanisms – Puffballs and Pilobolus fungi use high-pressure release to shoot spores into the air.
Insect Assistance – Some fungi, like stinkhorns, emit odors to attract insects that carry spores to new locations.
70
symbioses
close interactions between two organisms living together
71
Mutualistic interactions occur when
both organisms benefit
72
Parasitic/Pathogenic interactions are when
one organism benefits and the other is harmed
73
Commensalism occurs when
one organism benefits and the other is not affected
74
98% of lichen forming fungi are
ascomycetes
75
Lichen are mutualisms between a ___ and some type of ___
fungus (mycobiont); photosynthetic organism (photobiont - algae or cyanobacteria)
76
lichen relationship
In a lichen, the relationship between algae and fungi is a symbiotic mutualism, where the algae provides food through photosynthesis, while the fungus provides protection and a suitable environment for the algae to live in;
essentially, the algae feeds the fungus, and the fungus shelters the algae.
77
lichens can live in what environments
extreme (antartica)
78
who do lichen reproduce
fragmentation or by soredia
79
Lichen are ecologically important as pioneer species. what does this mean?
they produce acids that play an important role in rock weathering and soil formation
80
what is mycorrhize?
mutualistic associations between fungi
81
describe mycorrhize
Associations occur in the vast majority of vascular plants (>80%!)
Two types – endomycorrhizae and ectomycorrhiae
82
How do mycorrhizal fungi benefit from this relationship?
Nutrient Supply – They receive carbohydrates (mainly sugars like glucose and sucrose) from plants, which are products of photosynthesis. Since fungi cannot photosynthesize, this provides them with a vital energy source.
Habitat and Protection – The plant roots offer a stable environment for fungal growth and protection from environmental stress, such as drought or soil disturbances.
Reproductive Success – By forming extensive underground networks (mycelial networks), mycorrhizal fungi increase their ability to spread spores and colonize new plant hosts, ensuring their long-term survival and reproduction.
83
how do the plants benefit form the mycorrhizal relationship
Enhanced Nutrient Uptake – Mycorrhizal fungi extend their hyphae into the soil, increasing the plant’s access to essential nutrients like phosphorus, nitrogen, and micronutrients that would otherwise be difficult to absorb.
Improved Water Absorption – The fungal network helps plants access water more efficiently, especially in dry or nutrient-poor soils, improving drought resistance.
Increased Disease and Stress Resistance – Mycorrhizal fungi help protect plants from root pathogens by competing for space and resources. They also enhance plant immunity and tolerance to environmental stresses such as salinity, heavy metals, and extreme temperatures.
84
what does endomycorrhizae do
Fungal hyphae penetrate into root cells forming arbuscules – (fungi are aka arbuscular mycorrhizae) – greatly invaginate the plasma membrane, increasing surface area to facilitate transfer of nutrients
85
what is the most common type of mycorrhizae
endomycorrhizae is the Most common type of mycorrhizae (80% of associations with vascular plants)
86
what is endomycorrhizae fungus
Glomeromycete
87
what does ectomycorrhizae do
Hyphae grow between cells of the root epidermis and cortex forming the Hartig net. Also form a mantle or sheath that covers the root surface
88
describe ectomycorrhizae
Common in temperate shrubs and trees, Fungi are most commonly basidiomycetes, but some ascomycetes (truffles and morels!)
89
how do orchid seeds germinate?
only in the presence of mycorrhizae
90
effect of fungal plant pathogens
Fungal plant pathogens lead to big economic costs -- destroy about 1/3 of the world’s crops each year!
91
human fungal diseases
mycoses, mycotoxins
92
what is mycoses
parasitic infection of fungi
93
common types of mycoses
ringworm, athlete’s foot, yeast infection (Candida)
94
immunocompromised people affected by what diseases from mycoses
aspergillosis, fungal pneumonia, fungal meningitis, microsporidiosis
95
what are mycotoxins/mycotoxicoses
secondary metabolites that may cause disease or death in humans
96
types of mycotoxicoses
Aflatoxins, fumonisins, ergot
97
describe ringworm
40 different types of fungi cause ringworm
Generally called dermatophytosis – fungi are eating the skin
98
described aspergillosis
caused by Aspergillus, accounts for ~600,000 deaths annually worldwide
99
describe candida auris
Closely related to Candida albicans
Increase in infections linked to climate change
Mortality rates - 30-70%
100
why is candida auris a problem
antifungal resistance
persistence on medical devices/human skin
invasive infection
identification challenge
101
aflatoxins are common mycotoxins produced by
Aspergillus that are found in common crops
102
what are aflatoxins
Highly carcinogenic
* Most toxic to children, but can
cause sickness or death in
adults too → liver damage
* Levels are now highly regulated
in food and feed
103
what is ergotism caused by
Ergotism caused by Claviceps fungi infecting rye
104
what is claviceps
Contains an alkaloid (LSA – precursor to LSD!) that causes convulsive symptoms, such as tingling in the fingers, vertigo, headaches, disturbances in sensation, hallucination, painful muscular contractions, vomiting and diarrhea, as well as psychological symptoms, such as mania, psychosis, and delirium.
105
fungi and the human microbiome
Shotgun metagenomics sequencing approaches suggest that fungi
account for approximately 0.1% of the gut microbiome
106
Candida albicans is an important part of the human microbiome, why?
Microbial Balance – Candida competes with other microbes in the gut, mouth, and skin, helping to maintain a balanced microbial ecosystem.
Immune System Regulation – Low levels of Candida help train the immune system, keeping it responsive to potential fungal infections.
Digestive Processes – While not a major contributor, Candida interacts with gut bacteria and may aid in breaking down certain nutrients.
107
fungi as medicine
Antibiotics
Lovastatin
Cyclosporin
‘magic mushrooms’
Ancient Chinese medicine: Cordyceps and many others
108
what are antibiotics
Antibiotics are compounds produced by fungi or bacteria that kill or limit bacterial growth
109
antibiotics discovery
Alexander Fleming, 1928
* Plates of Staphylococcus that were
contaminated with Penicillium
fungus
* Led to large scale production of
antibiotic by WWII
110
what is lovastatin
Lovastatin is an inhibitor of HMG-CoA reductase, the enzyme that catalyzes the conversion of HMG-CoA to mevalonate
111
how does lovastatin interact with cholesterol
Mevalonate is a building block of cholesterol biosynthesis, lovastatin interferes with its production by acting as a reversible competitive inhibitor of the enzyme
112
how was lovestatin derived
isolated from fermentation broth of an Aspergillus strain
113
what is cyclosporine
immunosuppressant drug
114
what is cyclosporine produced from
tolypocladium inflates (ascomycete)
115
how does cyclosporine work
Lowers the activity of T-cells; acts in the calcineurin pathway, decreases inflammation
116
what is cyclosporine used for
Used to prevent organ rejection in organ transplant patients, treat psoriasis, Crohn’s disease, rheumatoid arthritis
117
what are magic mushrooms
Magic mushrooms from the genus Psilocybe contain hallucinogenic compounds called psilocybins
118
what are magic mushrooms used for?
Used during religious and spiritual
ceremonies by some Native
American groups for thousands of
years
Current research for use treating
depression, anxiety, and drug
dependence
119
what are cordyceps
Cordyceps fungus parasitizes insect hosts, but has been used for thousands of years in Chinese medicine
120
what is the biggest mushroom?
Armillaria ostoyae (honey mushroom) actually kills trees in its path
121
what is fungal bioremediation
Fungal Bioremediation – biological process to transform/degrade/sequester/remove an undesired chemical from the environment
122
poisonous mushrooms
Approximately 1-2% of mushrooms are believed to be poisonous
Must be ingested to cause harm
123
most deadly fungal poison
amanitin
124
Recent data shows the genetic locus for producing amanitin was transferred via
horizonal gene transfer!
125
Are fungal cells totipotent?
yes: mycelial culture can be produced in vitro from a fragment of a mature, fully differentiated structure, e.g. a fruit body stem
except for meiocytes
126
difference between endomycorrhizae and ectomycorrhizae visually
endomycorrhizae has pockets that are pink
ectomycorrhizae has empty pockets
127
how many species of Lichen
two* species from two different kingdoms
128
what is fermentation
Fermentation is an anaerobic process that allows various organisms to make ATP from simple sugars, and leads to the production of either CO2 and ethanol or lactic acid
129
The history of alcohol
yeast needs simple sugars (glucose, fructose) – so wine was probably the first alcoholic beverage made ~10,000 years ago – the more sugar in the substrate, the more fermentation and more alcohol
130
Most yeasts used for making alcoholic beverages and bread come from the
___ family
Saccharomyces
131
If wine is made from grapes, what is beer made from?
wheat
132
what does amylase do in beer production
breaking down starches into fermentable sugars, which yeast then converts into alcohol and carbon dioxide
133
Most beer is made with
Saccaromyces
134
sour beer is made with ___
Brettanomyces, Lactobacillus and Pediococcus are most common
Some use open air fermenters and other wild yeasts
135
what is bourbon and synthesis fungi
Bourbon is a mix of corn, rye, and malted barley
Saccaromyces is again the main fermentation yeast, but every distillery has their own strains that have distinct flavor profiles
136
Whiskey fungus
(Baudoinia compniacensis) is a black, sooty mold that thrives in areas near distilleries, aging warehouses, and spirit production facilities. It grows on buildings, trees, and other surfaces exposed to airborne ethanol, which evaporates during the aging process of whiskey, bourbon, and other distilled spirits.
137
what is the fungus in bleu cheese
penicillium roquefortii
138
foods fungus can be used in
bread, cheese, soy sauce
139
Is eating meat bad for the environment?
Yes, eating meat has a significant environmental impact. Meat production, especially from cattle, contributes to:
Greenhouse Gas Emissions – Livestock produce methane, a potent greenhouse gas.
Deforestation – Forests are cleared for grazing and feed crops, reducing biodiversity.
Water and Land Use – Meat requires more water and land compared to plant-based foods.
140
meat alternatives
Mycoprotein (e.g., Quorn) is made from Fusarium fungi and mimics meat texture.
Mushrooms (like portobello and shiitake) are used as natural meat substitutes.
