Categorie: Tutti - decomposers - fungi - diseases - reproduction

da Krishna Kasabwala mancano 5 anni

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Fungi

Fungi are a diverse group of organisms with complex reproductive and symbiotic mechanisms. They reproduce through both sexual and asexual means, utilizing spores, meiosis, mitosis, and budding.

Fungi

Fungi

Zygomycota

Zygosporangium (karyogamy and meiosis occur)
Zygospores
Karyogamy( haploid nuclei fuse from two different parents and produce diploid cells)
multicellular

When conditions are good, sexual reproduction occurs(meiosis) and the zygosporangium germinates into a sporangium

Sporangiophores (a hypha bearing sporangia)

Zygosporess form in zygosporangium and can be shot in certain types of fungi (ex: pilobolus)

Hyphae are coenocytic (no septate)
septate (cross walls that divide fungi into cells)
Molds
Black Bread Mold (Rhizopus stolonifer)

Rhizoids (rootlike parts of hyphae that anchor the fungus)

Stolons (horizontal hypae that connect groups of hyphae)

Zygomycetes

Glomeromycota

Form Arbuscular(Endo) mycorrhizae
Arbuscular mycorrhizae (another word for haustoria mycorrhizae)
(fungal mycelia penetrate root cells)
Glomeromycetes

Chytridiomycota

Include both multi-cellular and unicellular species
Have cell walls made of chitin
Some form colonies with hyphae, while some are single spherical cells
Chytrids
Have flagellated spores called zoospores

Characteristics of all Fungi

Fungi that causes diseases
Claviceps purpurea

rye

Fusarium Circinatum

pine

plant pathogens

Cryphonectria parasiticia

chesnut

Practical uses of Fungi
research
alcohol
medicine
food
Reproduction
Sexual

meiosis

spores

Asexual

Mitosis

budding

pinching of cells

yeast

fragmentation

fungi splits into fragments

Hyphae
Pseudohyphae

form by yeasts

incomplete budding causes elongated cells that haven't divided

Budding

Conenocytic
Septate
Mycorrhizae
Ectomycorrhizae

form sheaths of hypae over root

Abuscular
Symbiotic Relationships
Endophytes (fungi that lives in plant leaves or other parts that are beneficial

Are usually Ascomycetes

Absorptive Heterotrops
Enzymes are used to break down a large variety of complex molecules into smaller organic compounds

Lichen

Soridia
small clusters of hyphae with embedded algae
Ascomycete species that live with green algae or cyanobacteria in symbiotic relationships
Fruticose

shrublike

Foliose

leaflike

Crustose

grow on rocks

Ascomycota

Neurospora crassa (Bread Mold)
reproduce asexually by producing by producing conidia spores

Conidia (produced externally at the tips of specialized hyphae called conidiophores)

Fusion of two different mating types is followed by plasmogamy (union of 2 parent mycelia)

dikaryotic cells with cells at tips develop into asci

meiosis occurs then mitosis to produce 8 ascospores

sexual reproduction

Some form Mycorrhizae (mutual relationship with plants) (mycelia improve delivery of minerals to plants and plants supply fungi with organic nutrients
Symbiotic Relationship (lichen)
Ascocarps (fruiting body that holds asci)
Ascus (sac fungi) (sacs that contain the ascospores)

Ascospores (haploid spores) (sexaul)

Ascomycetes

Basidiomycota

Parasitic plant parasites
smuts
rusts
Club Fungi
Mushrooms
Puffballs

Subtopic

Shelf Fungi

decomposers break down lignin (complex polymer in wood)

Basidiocarps (fruiting bodies that allow mycellium to reproduce sexually)
After a mushroom forms, cap supports/protects large dikaryotic basida on gills

Basida (spore bearing structure)

Basidiospores (meiosis produces 4 haploid nuclei which develop into a basidiospore)

Gills (means of spore dispersal)

Fairy Rings (growth is concentrated in hyphae musrooms pop up in a ring shape as it absorbs water and as cytoplasm streams in from diaryotic mycelium)

Diaryotic mycellium (2 nuclei divide 1 after another without fusing)