7. Three forms of lichen (Know for lab
exam)
1. Crustose: crustlike, growing tight against the
substrate.
2. Foliose: leaflike, with flat sheets of tissue not
tightly bound
3. Fruticose: free-standing branching tubes.
9. Four Fungal diseases
1.
2.
3.
4.
Thrush: yeast infection
Histoplasmosis : lung infection
Aspergillosis : mold in your house
Cryptococcus /Valley fever: can lead to
pneumonia and meningitis
11. Sporotrichosis: rose gardener’s disease
• Fungal antibiotics are harmful; humans and
fungi are eukaryotes. Bacterial infections are
better to treat because they are prokaryotes
16. Structure
• Mycelia: networks of branched hyphae (cells)
• Septum (cell wall) separating the hyphae
• Coenocyte fungi lack septa and cellular
contents can flow between the hyphae
17. Septate hyphae
• Septum: a cross-wall
formed in association
with the mitotic division
of a cell, laid down
between the cells,
usually at regular
intervals.
19. Types of mycorrhizae fungi
• Ecto : grow into the extracellular species of
the root cortex (truffle)
• Endo: grow into the root cell (orchid)
20. Reproduction
• Plasmogamy: union of two parent mycelia
• Heterokaryon: cell or mycelium in some fungi
that do not result in the fusion of two nuclei
• Dikaryotic: the nucleus pair off two to a cell
21. Karyogamy (nuclear fusion)
• Produce diploid cells
• Takes a long time
• 2n phase is short-lived and undergo meiosis,
producing 1n spores
31. glomeromycota
• Arbuscular mycorrhizae: endo
• 80% of all vascular plants have arbuscular
mycorrhize
• Reproduce asexually
• Help plants absorb phosphorous and help a
crucial role in colonization of land by plants
32. Ascomycetes (cup fungi)
• Asci: sexual spores that are found in saclike
structure
• Reproduce sexually
• Many asci are found on the fruiting body
called ascocarp
• Ex. Truffle
• Conodia: asexual spores
• Conodiophore: structure
39. Reproduction of
Basidiomycetes: typical
mushroom
• Sexual mostly resulting in
dikaryotic fruiting bodies
called basidiocarps
(mushroom)
• Karygomy occurs in the gills
of the mushroom cap where
basidium and basidiophores
are found
• Asexual reproduction is rare
and occur via fragmentation
• Ex. Club fungi, rust, smut,
puff balls, shelf fungi,
mushrooms
40. Basidiomycete life cycle
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Basidiomycetes – Fungi
Key Points
The basidiomycetes (phylum Basidiomycota) are comprised of roughly
30,000 species that include mushrooms, shelf fungi and puffballs.
The basidium is a specific, club-shaped cell where karyogmay is carried out
followed by meiosis. This gives rise to the name club fungus.
A diploid nucleus is formed during karyogamy and then undergoes meiosis,
resulting in four haploid nuclei. The basidium divides into four arms, with a
single haploid nucleus in each that will develop into a basidiospore.
The reproductive cycle of basidiomycetes has a long dikaryotic mycelium
stage allowing for genetic diversity as a result of recombination.
Basidiomycetes are particularly important in nature as decomposers of
plant material, especially dead wood and trees.
Terms
basidium
a small structure, shaped like a club, found in the Basidiomycota phylum of
fungi, that bears four spores at the tips of small projections
Karyogamy
The fusion of two nuclei within a cell.
Mycelium
The vegetative part of any fungus, consisting of a mass of branching,
threadlike hyphae, often underground.
mycelium
the vegetative part of any fungus, consisting of a mass of branching,
threadlike hyphae, often underground
Mycelia: networks of branched hyphae (cells)the mass of interwoven filamentous hyphae that forms especially the vegetative portion of the thallus of a fungus and is often submerged in another body Septum (cell wall) separating the hyphaea dividing wall or membrane especially between bodily spaces or masses of soft tissue compare dissepimentCoenocyte fungi lack septa and cellular contents can flow between the hyphaemultinucleate mass of protoplasm resulting from repeated nuclear division unaccompanied by cell fission
a structure within which spores are produced
Lab exam
hytrids are unique among fungi in having a flagellated stage. They produce zoospores with a single flagellum, making them capable of active movement through water.Chytrids produce zoospores with a single flagellum, making them capable of active movement through water. Because of this, early taxonomists classified them as protists. According to rRNA sequences in ribosomes, the chytrids are the most primitive of the fungal phyla.zoosporean asexual spore of some algae and fungi
The life cycle of Rhizopusstolonifer is representative of zygomycete species. This cycle begins with the penetration of food surface by coenocytic hyphae in order to absorb nutrients. Septa are only found where reproductive cells are made.In the asexual phase, haploid spores form and develop in the sporangium (black bulbs at the tip of hyphae), are dispersed in the air, and land on food to germinate.During times of nutrient deficiencies, some mold can reproduce sexually. Different chemical markers are used for mating recognition between variable mycelia types. A zygosporangium is formed, which is the site of karyogamy and meiosis.The zygosporangium contains heterokaryotic cells with haploid nuclei; diploid nuclei follow karyogamy. When favorable conditions are restored, meiosis proceeds and diverse haploid spores are released.TermszygosporangiumA sporangium that produces a single zygospore. zygomycetean organism of the phylum Zygomycotacoenocytica multinucleate cell that can result from multiple nuclear divisions without their accompanying cytokinesisExamplesThe hyphae of zygomycetes spreading across leaf litter (Figure 1) is a component of the decomposition process. The species is Pliobolus, and it can aim the sporangia toward light.
Glomeromycetes are extremely important ecologically, forming nearly all arbuscular mycorrhizae, a critical association with plants.
Ascomycetes are the largest known group of fungi, occur in various ecosystems, and are very important ecologically, nutritionally, and medically.Asci are sac-like structures that contain spores and are present during sexual reproduction. Ascocarps are reproductive fruiting bodies that can be micro- or macroscopic.Conidia are asexual spores and are produced by conidiophores at the top of hyphae where they are dispersed into the air for distribution.Conidia can fuse with compatible mycelium to participate in sexual reproduction that includes plasmogamy and the formation of cells with haploid nuclei from each parent. Asci then develop at the hyphae tips resulting in four genetically diverse nuclei and ultimately eight ascospores.conidiaasexual, non-motile spores of a fungus and are named after the Greek word for dust, conia and are also know as conidiospores and mitosporesascocarpthe sporocarp of an ascomycete, typically bowl-shapedascomyceteany fungus of the phylum Ascomycota, characterized by the production of a sac, or ascus, which contains non-motile spores
Basidiomycetes: typical mushroom
Key PointsThe basidiomycetes (phylum Basidiomycota) are comprised of roughly 30,000 species that include mushrooms, shelf fungi and puffballs.The basidium is a specific, club-shaped cell where karyogmay is carried out followed by meiosis. This gives rise to the name club fungus.A diploid nucleus is formed during karyogamy and then undergoes meiosis, resulting in four haploid nuclei. The basidium divides into four arms, with a single haploid nucleus in each that will develop into a basidiospore.The reproductive cycle of basidiomycetes has a long dikaryotic mycelium stage allowing for genetic diversity as a result of recombination.Basidiomycetes are particularly important in nature as decomposers of plant material, especially dead wood and trees.Termsbasidiuma small structure, shaped like a club, found in the Basidiomycota phylum of fungi, that bears four spores at the tips of small projectionsKaryogamyThe fusion of two nuclei within a cell.MyceliumThe vegetative part of any fungus, consisting of a mass of branching, threadlike hyphae, often underground.myceliumthe vegetative part of any fungus, consisting of a mass of branching, threadlike hyphae, often underground
