Lecture 7&8 Flashcards
Fungi are heterotrophs. They secrete ___ that break down _____ into simpler compounds that the fungi absorb
enzymes
organic molecules
Fungi are __ or ___ They absorb nutrients from nonliving material
decomposers or saprobes
Some fungi are ___ they absorb nutrients from the cells of living hosts
parasitic
Some fungi are ____ they absorb nutrients from a living host but they reciprocate with functions beneficial to their partners
mutualistic
Multicellular fungi consist of long slender filaments called ____. Some are continuous others are divided by septa
hyphae
___ fungi consist of long slender filaments called hyphae. Some hyphae are continuous others are divided by seta
Multicellular
Hypha without septa are ____ while those with septa can have one or two nuclei per cell
multinucleate
Many hyphae form a
mycelium
All fungi have the presence of cell walls composed of
chitin
The separation of chromosomes occurs within the nucleus first, without disassembly of the nuclear membrane
Nuclear mitosis
Most fungi propagate by producing large number of spores either ___ or _____
asexually or sexually
1 cell
haploid
can divide through mitosis
unicellular in most cases
spores
Most fungi have a haplontic life cycle this means
the haploid generation is dominant
Fusion of the cytoplasm between hyphae of different mating types
Plasmogamy
During the ____ phase each cell has two nuclei that are genetically different
Dikaryotic (the extent of this stage varies among different phyla of fungi)
Fusion of nuclei which produces a zygote ( the zygote undergoes meiosis and produces sexual spores (n)
Karyogamy
Which of the following is FALSE about fungi
- THey are heterotrophic
- Some are unicellular
- They decompose organic matter
- Most fungi have a diplontic life cycle
- Fungi have nuclear mitosis
Most have a diplontic life cycle – this is not true they have a haplontic life cycle
____ descended from an aquatic, single-celled, flagellated protist
Fungi
Fungi live in many env from the tundra to the tropics and _____ envs
terrestrial
study fungi, estimate that there are about 1,5 million fungal species
mycologists
Kingdom fungi is divided into ____ phyla
8
- Obligate, intracellular, animal parasites
- Unicellular
- Long thought to be protists
- Lack mitochondria their ancestors lost the mitochondria
Microsporidia
- non flagellated zoospores
- some have a haplodiplontic life cycle
- Saprobes or parasites
- Live in soil or water
Blastocladiomycetes
Most are aquatic
Have flagellated spores called zoospores
SOme species form a mycelium others are unicellular
Some are saprobes others are parasites of protists, plants, or animals
Chytridiomycota
Digest plant biomass in mammalian herbivore rumens . Mammalian herbivores depends on fungi for sufficient calories
Neocallimastigomycota
___ brought cellulase gene from bacteria into Neocallimastix genome
Horizontal gene transfer
What is the best match between a phylum of fungi and a characteristic/event that applies to them
Neocallimastigomycota
Digest cellulose in the rumen
Commonly known as the bread molds and commonly cause fruit rot
Zygomycota
Asexual reproduction of zygomycota occurs via the formation of ____
sporangia
Sexual reproduction of zygomycota occurs when mycelia of different strains come in contact and form ____
gametangia
The gametangia of zygomycota contains several haploid nuclei and undergo ___ to form a zygosporangium
plasmogamy
When conditions are favorable the zygosporangium germinates and ____
meiosis occurs resulting in the formation of spores
- A tiny group of monophyletic fungi
- Only asexual reproduction
- Form intracellular associations with plant roots called arbuscular mycorrhizae
- More than 200,000 species of plants form associations with this fungi
- they help plants to absorb water and nutrients particularly phosphorus
Glomeromycota
- Consists of mushrooms, toadstools, puffballs,
- Asexual reproduction sometimes occurs but fragmentation of hyphae or formation of spores
Basidiomycota
Asexual reproduction of Basidiomycota. Mycelia of different strains undergo plasmogamy resulting in a ____
heterokaryotic stage
The heterokaryotic stage of Basidiomycota forms a _____
basidiocarp (mushroom) with gills and basidia
Occurs in the basidia resulting in the formation of zygotes
Karyogamy
In Basidiomycota the zygote undergoes ___ leading to the formation of ____ (n)
meiosis
basidiospores
Basidiomycota are mainly saprobes but some obtain C from a
living hosts
Uses for mushrooms mentioned in lecture
Edible mushrooms
Poisonous mushrooms
Hallucinogenic mushrooms
Agaricus bisporus (mushroom)
edible mushroom
Amanita phalloides (mushroom)
death cap mushroom, poisonous
How is the death cap mushroom poisonous
The Amatoxins inhibit mRNA synthesis
Amanita muscaria (fly agaric) (mushroom)
Hallucinogenic mushroom
Rust and smuts are _____ of Basidiomycota
plant pathogens
This phylum includes morels, cup fungi, and some yeasts
Ascomycota
Asexual reproduction of Ascomycota occurs via the formation of ____
conidiophores
Sexual reproduction of Ascomycota. Mycelia of different strains undergo plasmogamy resulting in a _____ stage
heterokaryotic
The heterokaryotic stage of Ascomycota form an ____ with ___ where karyogamy occurs to form a zygote
ascocarp
asci
The Ascomycota zygote undergoes meiosis resulting in the formation of ____
ascospores(n)
Ascomycota are mainly saprobes but some obtain C and energy from ____
a living host
Example of Ascomycota. They develop entirely underground in association with the roots of some trees (oak and hazlenut)
Truffles
Example of Ascomycota. This fungus contaminates the grains of rye and other cereals. Contains many toxic metabolites that cause constriction of blood vessels resulting in gangrene,
Ergot
Example of Ascomycota. This fungus produces aflotoxins (carcinogenic) in corn and peanuts
A. flavus
Example of Ascomycota. This fungus causes ringworm and athlete’s foot.
Tinea
Very important example of Ascomycota. Asexual reproduction is by binary fission or budding. Many have sexualreproductions
Yeast (S. cerevisiae)
S. cerevisiae (yeast) is a facultative ____
anaerobe
In the presence of oxygen S. cerevisiae oxidizes ___
Under anaerobic conditions it ferments ____
sugars to CO2
sugar into alcohol
Pathogenic yeasts.Candida causes various types of
yeast infections
What are three mutualistic associations of fungi discussed in lecture
Neocallimastigomycota and ruminants
A. mycorrhizae and plants
Some fungi and ant colonies (food source)
A lichen is a symbiotic relationship between ____
a photosynthetic organism held in a mesh of fungal hyphae
The photosynthetic component of lichen is
cyanobacteria or unicellular green algae
The fungal component of lichen is
an ascomycota or basidiomycota
