Quiz 2

Question 1

differentiate btwn mitotic + meiotic spores and their biological significance

Answer 1

mitosis: asexual
meiotic:
- basidiomycota- sexual basidiospores
- ascomycota- sexual ascospore

Question 2

basidiocarp

Answer 2

structure that produces basidiospores/ascospores

Question 3

pleiotrophy

Answer 3

fungi that produce BOTH MEIOTIC AND MITOTIC spores

Question 4

Classify dikaryotic Fungi into phyla based on the sexual structures they produce.

Answer 4

Ascomycota
sac-like asci
Basidiomycota
club shaped basidia

Question 5

List and describe the shared characteristics across the Kingdom Fungi.

Answer 5

eukaryotic heterotroph that digests nutrients externally by secreting enzymes
- shared biochemical characteristics:
chitin in cell walls
cell membranes have ergosterol (vs animal sterol: cholesterol)
use (AAA) pathway to produce lysine
UGA codes for tryptophan in their mitochondrial genome

Question 6

Ophistokonts

Answer 6

“Clade” of fungi and animals
- referring to posterially attached flagellum (think of sperm and choanocytes in sea sponges)
- chitin POSSIBLY present
- storage of glycogen

Question 7

List the phyla and explain the characteristics associated with the Subkingdom Dikarya. How does this subkingdom differ from other major phyla in the Kingdom Fungi?

Answer 7

contains basidio- and ascomycota
- regularly septate hyphae
- dikaryotic stages in life

Question 8

Identify the taxonomic hierarchy of a given fungal group based on the suffix provided.

Answer 8

division: -mycota
sub-division: mycotina
class: -mycetes
sub-class: -mycetidae
order: -ales
family: -aceae

Question 9

Illustrate a phylogenetic tree showing the evolutionary relationship between the major dikaryotic groups compared to the rest of the Fungal kingdom.

Answer 9

see phone

Question 10

Diagram and explain the life cycle of a dikaryotic fungus. Explain how this life cycle would differ between the Basidiomycota and Ascomycota using the appropriate terminology for sexual structures. Be sure to be able to differentiate between plasmogamy, karyogamy & meiosis, and place them in the appropriate location on the life cycle.

Answer 10

dikaryotic: n + n
- 2 haploid nuclei within a single cell
diploid stage, haploid stage, meiosis
see phone for cycle picture
Basidia are dikaryotic (2 haploid nuclei)
Karyogamy: fusion of 2 haploid nuclei into a diploid nucleus (happens within basidia)
Diploid nucleus produces 4 new haploid spores through meiosis (basidiospores)
Released and grow into haploid mycelium
Plasmogamy: 2 different mating types of the haploid mycelium meet and form a dikaryotic mycelium
Develop into a basidiocarp (mushroom)

Question 11

Differentiate between Heterothallic and Homothallic mating systems in the Dikarya.

Answer 11

Heterothallic: individuals must vary at 1 or more loci in order to undergo sexual reproduction
Homothallic: form of self-fertilization- single haploid fungus can produce meiotic spores through self-fertilization
- create spores
- aka apomixis

Question 12

Symbionts
- fungal examples?

Answer 12

Symbionts
- mutualists: lichens, mycorrhizal fungus
- commensals
- parasites: biotrophs (feed on cells), necrotrophs (kill cells), anf hemibiotrophs (intermediate)

Question 13

Saprobes
- fungal examples?

Answer 13

Saprobes: decomposers
- soil fungi
- Degrade cellulose and other carbohydrates efficiently
- wood decay in fungi capable of lignin degradation
- can dominate harsh envis (hot, cold, dry, high solute conc)
- eg: - compost fungi are thermophilic

Question 14

Illustrate a tree of, and differentiate between, the three major subphyla in the Basidiomycota.

Answer 14

Agaricomycotina- diverse basidiomycota- mostly producing conspicuous fruiting bodies
Ustilaginomycotina- mostly plant associated: smuts, yeasts, etc
Pucciniomycotina- mostly plant related- rusts, yeasts, etc

Agar and Ustil share a common ancestor

Question 15

Summarize the general characteristics of the Phylum Basidiomycota.

Answer 15

Basidia + basidiospores
Usually have an extended dikaryotic phase
Septae close because of swelling of parenthosomes (as opposed to Woronin bodies blocking space between the septae
Form clamps

Question 16

Define clamp connection, and describe its purpose & how it forms

Answer 16

Used to maintain dikaryotic nature of the cells after meiosis occurs

Question 17

How does a morphological group compare to a taxonomic group?

Answer 17

morphological are based on superficial appearance and functions, while taxonomic groupings consider genome similarities and differences

Question 18

Differentiate between the three major morphological groups within the Subphylum Agaricomycotina

Answer 18

Hymenomycetes- forcibly eject basidiospores form hymenium
Gasteromycetes- passively release basidiospores into a cavity called a gleba that usually releases them passively
Jelly fungi- ancestral Agaricomycotina with gelatinous basidiomycota

Question 19

Differentiate between the two major morphological groups within the “Hymenomycetes”. Be able to identify which group examples of “Hymenomycetes” fall into.

Answer 19

Agaricales- mushrooms + boletes
Aphyllophorales- polypores, corals, clubs, chanterelles

Question 20

List the major groups of “Gasteromycetes” and describe how this group differs from “Hymenomycetes”. How is it the same?

Answer 20

Gasteromycetes- well-defined hymenium of basidia, exposed prior to spore maturation
Both fleshy forest fungi
- puffballs
- stalked puffballs
- earth stars
- stinkhorns
- bird’s nest fungi
- artillery fungus
“secotioid fungi”