Fungi

What are Fungi

-Eukaryotes, and multicellular

-Nuclei of fungal hyphae and spores are haploid, except for transient diploid

How do fungi eat

-Absorption

-exoenzymes 

Exoenzymes 

-Hydrolytic enzymes secreted by the fungus, digest food outside its body to simpler compounds 

-saprobes  

-digestion outside of body, decomposes organic substances

Saprobic fugi

-Absorb nutrients from nonliving organism 

-outside of body digestion

Parasitic fugi

-absorb nutrients from the cells of living hosts (preying on animals)

-hyphae modified haustoria

Mutualistic fungi

absorb nutrients from a host organism, they reciprocate with functions that benefit their partner 

Fugal hyphae

-cell walls are made of chitin

-multicellular with hyphae divided into cells by cross walls (septa) 

-pores large enough for ribosomes 

-vegetative body of fungus 

Coenocytic fungi 

-continuous cytoplasm mass

-hundreds or thousands of nuclei

-repeated nuclear division without cytoplasmic division 

Mold

-rapidly growing, asexually reproducing fungus

-mycelia grow as saprobes or parasites on variety of substrates

-ONLY ASEXUAL STAGE, aesexual spores 

-fugus may reproduce sexually, (zygosporangia, ascocarps, basildiocarps)

Yeasts 

-unicellular fungi that inhabits liquid/moist 

-simple cell division of budding off 

-some reproduce sexually, forming sci (ascomycota), basidia (basidiomycota), no known sexual phase (imperfect fungi) 

Lichens

-symbiotic association of photosynthetic microorganisms

-live in extreme environments 

-fungal hyphae provides most of the mass/shape/structure

Mycorrhizae

-mutualistic associations of plant roots and fungi

-mycelium from the mycorrhizae greatly increase the absorptive surface of the plant roots

-mycor (fungus, rrhizae(root)

Karyogamy

-Fusion of haploid nuclei contributed by two parents

-karyo- (nucleus), -gamy (marriage)

plasmogamy 

-cytoplasmic fusion by two parents 

-plasmo- (cytoplasm), -ogamy(marriage)

Heterokayotic

-fusion of two hyphae that have genetically different nuclei 

-nuclei may remain in separate parts of the same mycelium or exchange chromosomes and genes

-hetero-(different), -karyo- (nucleus)

Genetically heterogeneous

fusion of two hyphae that have genetically different nuclei

Phylum Chytridiomycota: Chytrids

-mainly aquatic

-saprobes, parasite protists, plants, and animals

-flagellated zoospores

-most primitive fungi

-absorptive mode nutrition have chitinous cell walls

-unicellular chytrids, form coenocytic hyphae

(coeno-(common, shared), -cyte(cell)

Phylum Zygomycota: Zygote fungi 

-terrestrial - living in soil, decaying plant/animal material

-zygomycete (zygote fungi) hyphae are coenocytic with septa found in reproductive structures 

-sexual stage

Phylum Glomeromycota

-arbuscular (arbuscul-small tree) mycorrhizae

-symbiotic with plant roots

-90% of plants have

-Glomero-(ball/mass), -mycota (fungus)

Phylum Ascomycota: Sac fungi

-unicellular yeasts —> morels

-plant pathogens

-saprobes of plant material

-sacs called asci

-half are mutualistic with algae to be lichens (mycorrhizae), or live between mesophyll cells to protect plant tissue from insects by releasing toxins

-extensive heterokayotic stage during formation of ascocarps

-Asco- (sac), -mycoya(fungi)

Ascomycetes

heterokaryotic during the formation of ascocarps

Ascocarps 

sac-like structure that holds the spores of sac fungi

Phylum Basidiomycota: Club fungi

-eukaryotic mycelia

-dikaryotic mycelium (two nucleus) 

-mushrooms, shelf, fungi, puffballs, rusts

-basidium, transient diploid stage (sexual reproduction)

-elaborate fruiting body called basidiocarp 

-basid- (base), -id- (small), -mycota (fungus)

Haustoria

nutrient absorbing hyphae tips that penetrate the tissues of their host

Fungal reproductition