Lecture 7 - Fungi and their Classification Flashcards
- molds, mushrooms, lichen component, rusts, smuts and yeasts
- comprise eukaryotes with remarkable diverse life histories that make essential contributions to the biosphere, human industry, medicine and research
fungi
examples of fungi
- molds
- mushroomds
- lichen component
- rusts
- smuts
- yeast
fungi are __ and absrob nutrients from outside of their body
heterotrophs
as __, they can decompose dead matter
saprotrophs
contributes to fungi’s ecological success
versatility
Diverse lifestyles of fungi
- decomposers
- parasites
- mutualists
most common body structures of fungi
- multicellular filaments
- single cells (yeast)
what does the morphology of multicellular fungi enhance
ability to absorb nutrients
has a similar function in fungi to the roots of plants
mycelium
each of the branching filaments that make up the mycelium of a fungus
hyphae
fungi cell walls are made of what
chitin
elaborate fruiting body of fungi
mushrooms
Two types of hyphae
- aerial
- anchored
portion of the mycelium that anchors the mold and absorbs nutrients
- vegetative mycelium
- composed of vegetative hyphae
portion that produces asexual reproductive spores
- aerial mycelium
- composed of aerial hyphae
Two forms of hyphae
- septate hyphae
- coenocytic hyphae
smore fungi have hyphae divided into cells by __
septa
lack septa
coenocytic fungi
specialized hyphae in fungi that allow them to penetrate the tissues of their host
haustoria
mutually beneficial relaitonships between fungi and plant roots
Mycorrhizae
- form sheath of hyphase over a root
- also grows into extracellular spaces of root cortex
Ectomycorrhizal fungi
extend hyphae through the cells walls of root cells and into tubes formed by invagination of root cell membrane
Arbuscular mycorrhizal fungi
other name for arbuscular mycorrhizal fungi
Endomycorrhizal fungi
- far more common type
- hyphae penetrate root cells
Endomycorrhizae
hyphae do not penetrate root cells
Ectomycorrhizae
how do fungi propagate themselves
producing vast numbers of spores (sexually or asexually)
when can fungi produce spores
different types of life cycles
fungal nucleus with haploid chromosomes
mycelium
sexual reproduction of fungi
- mycelium
- plasmogamy
- heterokaryotic stage
- karyogamy
- meisosis
- germination
fusion of two parent mycelia
plasmogamy
unfused nuclei from different parents
heterokaryotic stage
fusion of nuclei
karyogamy
asxual reproduction of fungi
- mycelium
- spore-producing structures
- germination
fungal nuclei are normally __, with the exception of transient diploid stages formed during the sexual life cycles
haploid
what does sexual reproduction require
fusion of hyphae from different mating types
- sexual signaling molecules
- used by fungi to communicate their mating type
pheromones
mycelium where the haploid cell nuclei from each parent do not fuse right away
heterokaryon
haploid nuclei pair off two to a cell
dikaryotic
how long can time pass before the occurence of karyogamy in fungi
- hours
- days
- even centuries
- short-lived phas
- undergoes meiosis
diploid phase
produce haploid spores by mitosis and form visible mycelia
molds
- other fungi that can reproduce asexually
- inhabit moist environments
yeasts
where do yeasts inhabit
moist environments
instead of producing spores, how do yeasts reproduce asexually
- simple cell division
- piching of “bud cells” from parent cell
- certain molds and yeasts which have no known sexual stage
- imperfect fungi
deuteromycetes
can reproduce asexually by fragmentation of their hyphae
filamentous fungi
formed from aerial hyphae and are used for both sexual and asexual reproduction
fungal spores
where are fungal spores formed from
aerial hyphae
- formed by aerial hyphae of one organism
- new organisms are identical to parent
asexual spores
Different types of asexual spores
- conidiospore
- chlamydospore
- sporangiospore
unicellular or multicellular spore that is not enclosed in a sac
conidiospore
thick-walled spore formed within a hyphal segment
chlamydospore
asexual spore formed within a sac (sporangium)
sporangiospore
enclosed capsule that contains spores produced in fungi and many more species
Sporangium
- formed by the fusion of nuclei from two opposite mating strains of the same species
- new organisms are different from both parents
sexual spores
the ancestor of fungi was probably what
single-celled, flagellated protist
clade formed by fungi, animals, and their protistan relatives
opisthokonts clade