Fungi

Question 1

What kind of eating do fungi do? How has this helped them?

Answer 1

• Absorptive heterotrophy (saprotrophic, mutualistic, or predatory)
• led to diversity of biochems and interactions with other orgonisms

Question 2

What sorts of things are fungi found in?

Answer 2

yeast, alcohol, feul, drugs –> pennecillium = greenish mold in fruit +cheese –> penecillin

Question 3

What sorts of diseases are caused by fungi?

Answer 3

Trichophyton rubrum --> athlete's foot
wheat rust
powdery mildew
Candida albicans = yeastinfection/ thrush
snake disease

Question 4

spotted lanternfly

Answer 4

-fungi act as biocontrol agent to keep this pest at bay

Question 5

• Fungi life cycle
• unique anatomical structures
• unicellular or multicellular?

Answer 5

• most are haploid or dikaryotic (n+n) for most of life with short diploid phase
• mlticellular ones are filamentous fith hyphae, making masses called mycelium –> organized = mushrooms–> unorganized = molds
• unicellular ones are yeasts and microsporidians

Question 6

fungal cells

Answer 6

• glycogen used for carb storage

- cell walls are mainly chitin

Question 7

fungal history

Answer 7

• earliest one in Cambrian: 544 mya
• earliest ascomycetes in Silurian: 440 mya
• earliest chytrids, zygomycetes, and basidiomycetes in Deconian: 400 mya
• PALEOZOIC RADIATION

Question 8

fungal phylogeny

Answer 8

• sister to choanoflagellates and animals
• chytrids were earliest diverging fungal lineage
• fungi include microsporidians

Question 9

Two types of hyphae

Answer 9

-septate or coenocytic

Question 10

fungal reproduction

Answer 10

Asexual:

• spores are produced in different ways
• hyphae can break off parent and grow seperately
• budding in yeast

Sexual:

• rare/unknown in some groups
• sporic meiosis or zygotic meiosis

Question 11

Naming

Answer 11

• mostly named based off reproductive structures (usually swimming gametes/spores)
• zygosporangia, basidia, asci

Question 12

microsporidia

• size
• cellularity
• feeding habits
• motitlity
• other fun facts

Answer 12

• among smallest eukaryotic cell (1-40 nm)
• unicellular fungi with chitin walls
• obligate intracellular parasites of animals (including humans)
• no motility
• no mitochondria –> mitosome
• complex parasitic life cycle

Question 13

Microsporidiosis

Answer 13

• infective form of microsporidia
• resistant, long living spore
• spore pokes out its polar tubule and infects cell
• injects infective sporoplasm into host thru the tubule
• sporoplasm multiplies thru merogony (binary fission) or schizogony (multiple fission)
• either free in cytoplasm or in parasitophorous vacuole
• microsporidia develop by sporogony into mature spores
• during sporogony, thick wall forms around spore, providing resistance to adverse environment conditions
• spores fill up host cell and then burst it to infect other cells
• affect a bunch of dif animals and are in GI of ppl (especially if immune compromised)
• some animals have it naturally and pass it on to ppl

Question 14

chytrids

• where?
• cellularity
• reproductive structures
• feeding styles

Answer 14

• usually aquatic (soil, pond, stream)
• some unicellular; multicellular ones are simple and form coenocytic filaments or rhizoids
• flagelated gametes (sexual) and zoospores (asexual)
• some are parasitic on plants/aquatic animals; many are saprophytic

Question 15

Allomyces

Answer 15

• chytrid
• alternation of gemerations life cycle with 2 morphologically similar phases: one haploid (gametophyte) and one diploid (sporophyte)

Question 16

chytridiomycosis

Answer 16

• caused by batachochytrium dendrobatidis
• non-hyphal chitrid
• zoospores penetrate skin and form zoosporangia
• grow in diameter and complexity
• discharge papillae
• infected amphibians die w/in 2 weeks
• cap lost and zoospores escape thru skin

Question 17

zygomycota

• where?
• hyphae?
• lifecycle type?
• reproduction?
• examples?

Answer 17

• mainly terrestrial –> some aquatic parasites
• coenocytic hyphae
• most of lifecycle is haploid
• asecual reproduction by spores in sporangia
• sexual spores are made in zygosporangium
• Rhizopus = black bread mold
• Pilobolus = dung fungus

Question 18

rhizopus life cycle

Answer 18

(2n) Fertilization
- zygospore

(n) Meiosis
- sporangiophore releases spores
- spores germinate to produce new mycelium
- compatible gametangia meet

(n+n) Plasmogamy
-zygosporangium

(2n) Fertilization

Question 19

Pilobus

Answer 19

• zygomycota
• sporangial ejection
• sporangiophores are phototacic–> they detect the direction of light and orient the sprangia toward light (blue light works best)
• sporangia are shot several m away
• adaptive significance –> fungi themselves aren’t photosynthetic

Question 20

Glomeromycota

Answer 20

• arbuscular mycorrhizal fungi
• coenoctic hyphae –> asexual spore production –> no known sexual reproduction
• associate with roots of plants (80-90% of plants have these associations)
• fungi get fixed carbon and plants get nutrients (esp K)

Question 21

Who does endomycorrhizal stuff and who does ectomycorrhizal stuff?

Answer 21

• glomeromycota does endo

- ascomycota and basidiomycota do ecto

Question 22

Ascomycota hyphae

Answer 22

-Hyphae septate with woronin bodies (small spheres with pores)

Question 23

Ascomycota asci

Answer 23

• contain ascospores
• naked asci is most primitiv
• derived forms make ascomata (fruiting bodies with asci)
• cleistothecial (circle)
• apothecial (unwound circle)
• perithecial (tear drop with open top)
• ascolocular (closed tear drop)

Question 24

Ascomycota life cycle

Answer 24

ascospores grow into mating structures

• join to make n+n structure with n hyphae
• ascoma (fruiting structure) with n+n asci
• nuclei fuse
• meiosis happens
• mitosis happens –> 8 ascospores

Question 25

conidia

Answer 25

-Usually ascomycota, but sometimes basidiomycota and zygomycota use it for asexual reproduction

Question 26

Saccharomyces

Answer 26

- single celled fungi - replicate thru budding (asexual) - replicate through ascospores (sexual) - dimorphic - bakers yeast

Question 27

Pathogenic ascomycetes

Answer 27

- candida = yeast infection - geomyces = white nose syndrome (95% mortality) - ophiostoma ulmi and bark beetle = dutch elm disease - cryphonectria parasticia = chestnut blight - cordyceps = zombies - ophiocordyceps sinesis = parasitizes ghost moth larva --> used in medicine - trichophyton = human dermatophytes - ergot = in wheat rye and if eaten causes hallucinations (from LSD), stomach cramps, and burning limbs --> st anthony's fire and salem witch

Question 28

mushroom forming ascomycetes

Answer 28

morels and truffles | -edible and toxic muschroms look alike

Question 29

basidiomycota (club fungi) - phylogeny - hyphae - forms - special structures

Answer 29

- sister to ascomycota - prolonged dikaryotic stage - septate hyphae - conidial, yeast, mushroom, lichen, and mycorrhizal types - basidiospores on basidium - many produce clamps and dolipore septa --> unique

Question 30

dolipore septum

Answer 30

hyphae are septate with pores --> more complex than ascomyota's

Question 31

clamps

Answer 31

maintain dikaryotic condition characteristic in many basidiomycota

Question 32

basidiomycota life cycle

Answer 32

fruiting body has n+n parts - those parts go thru karyogamy (fuse nuclei) - Meiosis --> 4 basidiospores n - -germinating basidiospores/primary mycelium - plasmogamy (fusing membranes) n+n - basidioma - basidioma with basidiocarp housing n+n structures

Question 33

basidiomycota plant pathogens

Answer 33

- bracket or shelf fungus = sign of widespread fungal infection --> some kill and then eat - rusts and smuts = fungal diseases of plants --> complex life cycles involving plants and insects - puccinia = wheat stem rust --> 2 hosts and several spore producing stages --> no clamps or muschrooms

Question 34

hen of the woods

Answer 34

used in east asian medicine

Question 35

basidiomycota human and animal pathogens

Answer 35

cryptococcus neoformans - opportunistic infective agent - forms polysaccride sheath in host cells - lung infections --> can lead to meningitis and encephalitis - common in immunocompromized ppl Malassezia -yeast that may be involved in pancreatic tumors

Question 36

lichens

Answer 36

- mutualistic associations between mcobiont (fungi) and photosynthetic organisms (cyanobacteria or green algae) - usually asco or basidio - soredia = photosynthetic cells wrapped in hyphae that travel thru air to form new lichens

Question 37

overview of fungi

Answer 37

• Sister to animals + choanoflagellates clade • Characterized by chitin cell walls • Basal groups include chytrids (motile) and microsporidians (parasitic) • Zygomycetes coenocytic (like chytrids) and characterized by production of a zygosporangium • Glomeromycota similar to zygomycetes; asexual • Most derived groups are the Dikarya (Ascomycota and Basidiomycota) characterized by production of dikaryons, cells that are dikaryotic (n+n) and give rise to sexual spores