Micro Ch 5 - Kingdom Fungi
Terms
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- are fungi eukaryotes or procaryotes?
- eucaryotes
- what are the two groups of species of fungi?
- macroscopic fungi and microscopic fungi
- what group of fungi are mushrooms a part of?
- macroscopic
- what group of fungi are puffballs a part of?
- macroscopic
- what group of fungi are gill fungi a part of?
- macroscopic
- what group of fungi are molds a part of?
- microscopic
- what group of fungi are yeasts a part of?
- microscopic
- what are the two morphologies of microscopic fungi?
- yeast or hyphae
- yeast
- round ovoid shaped, asexual reproduction
- hyphae
- long filamentous fungi or molds, they branch out too look for food
- dimorphic
-
microscopic fungi that exist in either yeast or hyphae form
*characteristic of some pathogenic molds - all fungi are...
- heterotrophic - they need another organism for nutrition - decaying material
- saprobes
- living off dead plants and animals
- fungal parasites
- live on the tissues of other organisms - none are obligate
- mycoses
- fungal infections
- what is the optimal growth temperature for fungi?
- 20-40 degrees Celsius
- where do fungi grow?
- extremely widespread distribution in many habitats
- what is the fungal organization of most fungi?
- most grow in loose associations or colonies
- what is the fungal organization of yeast?
- soft, uniform texture and appearance
- septate
- hyphae divided by cross walls
- vegetative hyphae
- digest and absorb nutrients
- reproductive hypae
- produce spores for reproduction
- mycelium
- mass of hyphae with cottony, hairy, or velvety texture
- how do fungi reproduce?
- primarily through spores formed on reproductive hyphae
- asexual reproduction of fungi
- spores are formed through budding or mitosis
- how does yeast grow?
- it swells on its surface called buds which then become separate cells
- pseudohypha
- a chain of yeasts formed when buds remain attached in a row
- substrates
- variety of organic material from which fungi acquire their nutrients
- nonseptate hyphae
- consist of one long continuous cell not divided into individual compartments by cross walls
- spores
- fungal reproductive structures
- sexual reproduction of fungi
- spores are formed following fusion of male and female strains and formation of sexual structures
- sporangiospores
-
formed by successive cleavages within a sac-like head called a sporangium, which is attached to a stalk, the sporangiophore
these spores are initially closed but are released when the sporangium ruptures - conidiospores
- free spores not enclosed by a spore-bearing sac. they develop either by the pinching off of the tip of a special fertile hypha or by the segmentation of a preexisting vegetative hypha
- which are the most common asexual spores?
- conidiospores
- what are the three most common sexual spores?
-
zygospores
ascospores
basidiospores - zygospores
- sturdy diploid spores formed when hyphae of two opposite strains (plus and minus strains) fuse and create a diploid zygote that swells and becomes covered by strong, spiny walls
- ascospores
- created in special fungal sac. formed when two different strains or sexes join together to produce offspring
- basiodiospores
- haploid sexual spores formed on the outside of a club-shaped cell called a basidium
- how are fungi identified in medical specimens?
- by first being isolated on special types of media and then being observed macroscopically and microscopically
- what are some categories for identification of fungi?
-
asexual spore-forming structures and spores
hyphal type
colony texture
pigmentation
physiological characteristics
genetic makeup - nearly all fungi are _____ and do not require a _____ to complete their life cycles.
-
free-living
host - what are the two main types of fungal pathogens that humans are not resistant to?
- primary pathogens and opportunistic pathogens
- opportunistic pathogens
- attack persons who are already weakened in some way
- what are beneficial impacts of fungi?
-
decomposers of dead plants and animals
sources of antibiotics, alcohol, organic acids, and vitamins
used in making foods and in genetic studies - why is the list of opportunistic fungal pathogens increasing?
- because of newer medical techniques that keep immunocompromied patients alive
- Aspergillus flavus
- a mold that synthesizes a potentially lethal poison called aflatoxin
- what does aflotoxin do? and where does it come from?
-
it causes a disease in domestic animals that have eaten grain that was contaminated witht he mold Aspergillus flavus
also causes liver cancer in humans - saccharomyces
- the yeast that produces the alcohol in beer and wine and the gas that causes bread to rise