ECOL 182R Exam 4 Questions With Correct
Answers
What is the overview of fungi? - CORRECT ANSWER✔✔-- fungi play critical roles
| | | | | | | | | | | | |
in terrestrial ecosystems
| |
- all fungi feed by absorption
| | | | |
- yeasts vs mycelium
| | |
- fungi often have unusual life cycles
| | | | | |
- fungal reproductive structures
| | |
- key fungal lineages
| | |
What are critical ecolgical roles of fungi? - CORRECT ANSWER✔✔-- critical in soil-
| | | | | | | | | | | |
plant interactions|
- primary decomposures in land ecosystems
| | | | |
- only eukaryote that can fully digest wood
| | | | | | |
What is an examples of soil-plant interactions as a critical ecological role of fungi?
| | | | | | | | | | | | |
- CORRECT ANSWER✔✔-- mycorrhizal fungi
| | | | |
What is an example of primary decomposures in land ecosystems as a critical
| | | | | | | | | | | | |
ecological role of fungi? - CORRECT ANSWER✔✔-- saprophytes are fungi that
| | | | | | | | | | |
make their living by digesting dead plant material
| | | | | | |
- critical agents in the land carbon cycle
| | | | | | |
,What is a hypothesis of the idea that only eukaryotes that can fully digest wood?
| | | | | | | | | | | | | |
|- CORRECT ANSWER✔✔-one hypothesis is that thick coal deposits laid down
| | | | | | | | | | |
during the Carboniferous period occurred because the swamps in which such
| | | | | | | | | | |
forests grew had too low a pH for fungi and hence the wood did not decompose
| | | | | | | | | | | | | | |
What disease do a few fungi cause? - CORRECT ANSWER✔✔-- plant diseases
| | | | | | | | | | | |
(rusts, mildews, blights) major impact on some crops
| | | | | | |
- a few human diseases (valley fever, athlete's foot, vagninitis, ringworm)
| | | | | | | | | |
What do fungi exist as? - CORRECT ANSWER✔✔-exists as single cells (yeasts) or
| | | | | | | | | | | | |
complex filaments (mycelia) | |
What are structures in the mycelia? - CORRECT ANSWER✔✔-- hyphae
| | | | | | | | |
- heterokaryon
|
- septa
|
What are hyphae? - CORRECT ANSWER✔✔-individual filaments
| | | | | |
What are heterokaryon? - CORRECT ANSWER✔✔-- most hyphae are haploid
| | | | | | | | |
- within a hyphae, for many species there can be two DISTINCT haploid nuclei
| | | | | | | | | | | | |
What are septa? - CORRECT ANSWER✔✔-- no true cell walls within the hyphae,
| | | | | | | | | | | | |
which have septa (holes)
| | |
- the mycelia is somewhere between a multicellular and a giant single-celled
| | | | | | | | | | | |
organism
,What are the characteristics of these structures in the mycelia? - CORRECT
| | | | | | | | | | | |
ANSWER✔✔-- since mycelia are composed of branching networks fo very thin
| | | | | | | | | | |
hyphae, fungi have very high surface-area-to-volume ratio; this makes absorption
| | | | | | | | | |
efficient and allows fungi to be prone to drying out
| | | | | | | | |
- fungi synthesize and secrete enzymes outside their hyphae; resulting
| | | | | | | | | |
compounds are absorbed by hyphae (extracellular digestion)
| | | | | |
- fungi have unusual life cycles, with sex occurring with mycelia or yeast of
| | | | | | | | | | | | | |
different mating types fusing | | |
What are the fungal life cycles? - CORRECT ANSWER✔✔-fertilization occurs in two
| | | | | | | | | | |
steps in many fungi:
| | | |
1. fusion of cells
| | |
2. fusion of nuclei from the fused cells
| | | | | | |
- these two steps can be separated in both time and space
| | | | | | | | | | |
plasmogamy
karyogamy
What is plasmogamy? - CORRECT ANSWER✔✔-occurs when the cytoplasm fuse;
| | | | | | | | | |
if the nuclei remain independent, the mycelium becomes heterokaryotic
| | | | | | | |
What are karyogamy? - CORRECT ANSWER✔✔-occurs when the nuclei fuse
| | | | | | | | |
What are the fungal reproductive structures? - CORRECT ANSWER✔✔-1. fungi
| | | | | | | | | |
don't have sexes, rather mating types
| | | | | |
, - a and alpha can mate (fuse to form a reproductive structure), but not "a" with
| | | | | | | | | | | | | | |
|"a" nor "alpha" with "alpha"
| | | |
2. gametes and spores with flagella
| | | | |
- zygosporangium
|
- basidia
|
-asci
What are zygosporangium? - CORRECT ANSWER✔✔-hyphae of different mating
| | | | | | | | |
types yoked together | |
What are basidia? - CORRECT ANSWER✔✔-spores formed on little pedestals
| | | | | | | | |
What are asci? - CORRECT ANSWER✔✔-spores formed in sacs
| | | | | | | |
What are the reproductive structures used to classify fungi? - CORRECT
| | | | | | | | | | |
ANSWER✔✔-1. Chytridiomycota (chytrids) | |
- only fungi with motile cels, as they produce spores and gametes with flagella
| | | | | | | | | | | | |
2. Zygomycota
|
- zygosporangium
|
3. Basidiomycota (club fungi)
| | |
- basidia form at the ends of hyphae and produce spores
| | | | | | | | | |
4. ascomycota (sack fungi)
| | |
- tips of hyphae produce distinctive sacklike cells, called asci, that generate
| | | | | | | | | | | |
species
Answers
What is the overview of fungi? - CORRECT ANSWER✔✔-- fungi play critical roles
| | | | | | | | | | | | |
in terrestrial ecosystems
| |
- all fungi feed by absorption
| | | | |
- yeasts vs mycelium
| | |
- fungi often have unusual life cycles
| | | | | |
- fungal reproductive structures
| | |
- key fungal lineages
| | |
What are critical ecolgical roles of fungi? - CORRECT ANSWER✔✔-- critical in soil-
| | | | | | | | | | | |
plant interactions|
- primary decomposures in land ecosystems
| | | | |
- only eukaryote that can fully digest wood
| | | | | | |
What is an examples of soil-plant interactions as a critical ecological role of fungi?
| | | | | | | | | | | | |
- CORRECT ANSWER✔✔-- mycorrhizal fungi
| | | | |
What is an example of primary decomposures in land ecosystems as a critical
| | | | | | | | | | | | |
ecological role of fungi? - CORRECT ANSWER✔✔-- saprophytes are fungi that
| | | | | | | | | | |
make their living by digesting dead plant material
| | | | | | |
- critical agents in the land carbon cycle
| | | | | | |
,What is a hypothesis of the idea that only eukaryotes that can fully digest wood?
| | | | | | | | | | | | | |
|- CORRECT ANSWER✔✔-one hypothesis is that thick coal deposits laid down
| | | | | | | | | | |
during the Carboniferous period occurred because the swamps in which such
| | | | | | | | | | |
forests grew had too low a pH for fungi and hence the wood did not decompose
| | | | | | | | | | | | | | |
What disease do a few fungi cause? - CORRECT ANSWER✔✔-- plant diseases
| | | | | | | | | | | |
(rusts, mildews, blights) major impact on some crops
| | | | | | |
- a few human diseases (valley fever, athlete's foot, vagninitis, ringworm)
| | | | | | | | | |
What do fungi exist as? - CORRECT ANSWER✔✔-exists as single cells (yeasts) or
| | | | | | | | | | | | |
complex filaments (mycelia) | |
What are structures in the mycelia? - CORRECT ANSWER✔✔-- hyphae
| | | | | | | | |
- heterokaryon
|
- septa
|
What are hyphae? - CORRECT ANSWER✔✔-individual filaments
| | | | | |
What are heterokaryon? - CORRECT ANSWER✔✔-- most hyphae are haploid
| | | | | | | | |
- within a hyphae, for many species there can be two DISTINCT haploid nuclei
| | | | | | | | | | | | |
What are septa? - CORRECT ANSWER✔✔-- no true cell walls within the hyphae,
| | | | | | | | | | | | |
which have septa (holes)
| | |
- the mycelia is somewhere between a multicellular and a giant single-celled
| | | | | | | | | | | |
organism
,What are the characteristics of these structures in the mycelia? - CORRECT
| | | | | | | | | | | |
ANSWER✔✔-- since mycelia are composed of branching networks fo very thin
| | | | | | | | | | |
hyphae, fungi have very high surface-area-to-volume ratio; this makes absorption
| | | | | | | | | |
efficient and allows fungi to be prone to drying out
| | | | | | | | |
- fungi synthesize and secrete enzymes outside their hyphae; resulting
| | | | | | | | | |
compounds are absorbed by hyphae (extracellular digestion)
| | | | | |
- fungi have unusual life cycles, with sex occurring with mycelia or yeast of
| | | | | | | | | | | | | |
different mating types fusing | | |
What are the fungal life cycles? - CORRECT ANSWER✔✔-fertilization occurs in two
| | | | | | | | | | |
steps in many fungi:
| | | |
1. fusion of cells
| | |
2. fusion of nuclei from the fused cells
| | | | | | |
- these two steps can be separated in both time and space
| | | | | | | | | | |
plasmogamy
karyogamy
What is plasmogamy? - CORRECT ANSWER✔✔-occurs when the cytoplasm fuse;
| | | | | | | | | |
if the nuclei remain independent, the mycelium becomes heterokaryotic
| | | | | | | |
What are karyogamy? - CORRECT ANSWER✔✔-occurs when the nuclei fuse
| | | | | | | | |
What are the fungal reproductive structures? - CORRECT ANSWER✔✔-1. fungi
| | | | | | | | | |
don't have sexes, rather mating types
| | | | | |
, - a and alpha can mate (fuse to form a reproductive structure), but not "a" with
| | | | | | | | | | | | | | |
|"a" nor "alpha" with "alpha"
| | | |
2. gametes and spores with flagella
| | | | |
- zygosporangium
|
- basidia
|
-asci
What are zygosporangium? - CORRECT ANSWER✔✔-hyphae of different mating
| | | | | | | | |
types yoked together | |
What are basidia? - CORRECT ANSWER✔✔-spores formed on little pedestals
| | | | | | | | |
What are asci? - CORRECT ANSWER✔✔-spores formed in sacs
| | | | | | | |
What are the reproductive structures used to classify fungi? - CORRECT
| | | | | | | | | | |
ANSWER✔✔-1. Chytridiomycota (chytrids) | |
- only fungi with motile cels, as they produce spores and gametes with flagella
| | | | | | | | | | | | |
2. Zygomycota
|
- zygosporangium
|
3. Basidiomycota (club fungi)
| | |
- basidia form at the ends of hyphae and produce spores
| | | | | | | | | |
4. ascomycota (sack fungi)
| | |
- tips of hyphae produce distinctive sacklike cells, called asci, that generate
| | | | | | | | | | | |
species
