Chapter 31 - Fungi

Question 1

If all fungi in an environment that perform decomposition were to suddenly die, then which group of organisms should benefit most, due to the fact that their fungal competitors have been removed?

A) plants
B) protists
C) prokaryotes
D) animals
E) mutualistic fungi

Answer 1

C) prokaryotes

Question 2

When a mycelium infiltrates an unexploited source of dead organic matter, what are most likely to appear within the food source soon thereafter?

A) fungal haustoria
B) soredia
C) fungal enzymes
D) increased oxygen levels
E) larger bacterial populations

Answer 2

C) fungal enzymes

Question 3

Which of the following is a characteristic of hyphate fungi (fungi featuring hyphae)?

A) They acquire their nutrients by phagocytosis.
B) Their body plan is a unicellular sphere.
C) Their cell walls consist mainly of cellulose microfibrils.
D) They are adapted for rapid directional growth to new food sources.
E) They reproduce asexually by a process known as budding.

Answer 3

D) They are adapted for rapid directional growth to new food sources.

Question 4

The functional significance of porous septa in certain fungal hyphae is most similar to that represented by which pair of structures in animal cells and plant cells, respectively?

A) desmosomestonoplasts
B) gap junctionsplasmodesmata
C) tight junctionsplastids
D) centriolesplastids
E) flagellacentral vacuoles

Answer 4

B) gap junctionsplasmodesmata

Question 5

What do fungi and arthropods have in common?

A) Both groups are commonly coenocytic.
B) The haploid state is dominant in both groups.
C) Both groups are predominantly heterotrophs that ingest their food.
D) The protective coats of both groups are made of chitin.
E) Both groups have cell walls.

Answer 5

D) The protective coats of both groups are made of chitin.

Question 6

In septate fungi, what structures allow cytoplasmic streaming to distribute needed nutrients, synthesized compounds, and organelles throughout the hyphae?
A) multiple chitinous layers in cross-walls
B) pores in cross-walls
C) complex microtubular cytoskeletons
D) two nuclei
E) tight junctions that form in cross-walls between cells

Answer 6

B) pores in cross-walls

Question 7

What accounts most directly for the extremely fast growth of a fungal mycelium?

A) rapid distribution of synthesized proteins by cytoplasmic streaming
B) a long tubular body shape
C) the readily available nutrients from their ingestive mode of nutrition
D) a dikaryotic condition that supplies greater amounts of proteins and nutrients

Answer 7

A) rapid distribution of synthesized proteins by cytoplasmic streaming

Question 8

The vegetative (nutritionally active) bodies of most fungi are

A) composed of hyphae.
B) referred to as a mycelium.
C) usually underground.
D) Three of these responses are correct.
E) Two of these responses are correct.

Answer 8

D) Three of these responses are correct.

Question 9

Consider two hyphae having equal dimensions: one from a septate species and the other from a coenocytic species. Compared with the septate species, the coenocytic species should have:

A) fewer nuclei.
B) more pores.
C) less chitin.
D) less cytoplasm.
E) reduced cytoplasmic streaming.

Answer 9

C) less chitin.

Question 10

Immediately after karyogamy occurs, which term applies?

A) plasmogamy
B) heterokaryotic
C) dikaryotic
D) diploid

Answer 10

D) diploid

Question 11

Which description does not apply equally well to both sexual and asexual spores?

A) have haploid nuclei
B) represent the dispersal stage
C) are produced by meiosis
D) upon germination, will subsequently undergo S phase and mitosis

Answer 11

C) are produced by meiosis

Question 12

Plasmogamy can directly result in which of the following?

1. cells with a single haploid nucleus
2. heterokaryotic cells
3. dikaryotic cells
4. cells with two diploid nuclei

A) 1 or 2
B) 1 or 3
C) 2 or 3
D) 2 or 4
E) 3 or 4

Answer 12

C) 2 or 3

Question 13

After cytokinesis occurs in budding yeasts, the daughter cell has a

A) smaller nucleus and more cytoplasm than the mother cell.
B) smaller nucleus and less cytoplasm than the mother cell.
C) larger nucleus and less cytoplasm than the mother cell.
D) similar nucleus and less cytoplasm than the mother cell.

Answer 13

D) similar nucleus and less cytoplasm than the mother cell.

Question 14

In most fungi, karyogamy does not immediately follow plasmogamy, which consequently

A) means that sexual reproduction can occur in specialized structures.
B) results in multiple diploid nuclei per cell.
C) allows fungi to reproduce asexually most of the time.
D) results in heterokaryotic or dikaryotic cells.
E) is strong support for the claim that fungi are not truly eukaryotic.

Answer 14

D) results in heterokaryotic or dikaryotic cells.

Question 15

If all of their nuclei are equally active transcriptionally, then the cells of both dikaryotic and heterokaryotic fungi, in terms of the gene products they can make, are essentially

A) haploid.
B) diploid.
C) alloploid.
D) completely homozygous.
E) completely hemizygous.

Answer 15

B) diploid.

Question 16

Which process occurs in fungi and has the opposite effect on a cell’s chromosome number than does meiosis I?

A) mitosis
B) plasmogamy
C) crossing over
D) binary fission
E) karyogamy

Answer 16

E) karyogamy

Question 17

Which of the following statements is true of deuteromycetes?

A) They are the second of five fungal phyla to have evolved.
B) They represent the phylum in which all the fungal components of lichens are classified.
C) They are the group of fungi that have, at present, no known sexual stage.
D) They are the group that includes molds, yeasts, and lichens.
E) They include the imperfect fungi that lack hyphae.

Answer 17

C) They are the group of fungi that have, at present, no known sexual stage.

Question 18

Fossil fungi date back to the origin and early evolution of plants. What combination of environmental and morphological change is similar in the evolution of both fungi and plants?

A) presence of “coal forests” and change in mode of nutrition
B) periods of drought and presence of filamentous body shape
C) predominance in swamps and presence of cellulose in cell walls
D) colonization of land and loss of flagellated cells
E) continental drift and mode of spore dispersal

Answer 18

D) colonization of land and loss of flagellated cells

Question 19

Which of the following characteristics is shared by both chytrids and other kinds of fungi?

A) presence of flagella
B) zoospores
C) autotrophic mode of nutrition
D) cell walls of cellulose
E) nucleotide sequences of several genes

Answer 19

E) nucleotide sequences of several genes

Question 20

The multicellular condition of animals and fungi seems to have arisen

A) due to common ancestry.
B) by convergent evolution.
C) by inheritance of acquired traits.
D) by natural means, and is a homology.
E) by serial endosymbioses.

Answer 20

B) by convergent evolution.

Question 21

Asexual reproduction in yeasts occurs by budding. Due to unequal cytokinesis, the “bud” cell receives less cytoplasm than the parent cell. Which of the following should be true of the smaller cell until it reaches the size of the larger cell?

A) It should produce fewer fermentation products per unit time.
B) It should produce ribosomal RNA at a slower rate.
C) It should be transcriptionally less active.
D) It should have reduced motility.
E) It should have a smaller nucleus.

Answer 21

A) It should produce fewer fermentation products per unit time.

Question 22

Many infected animals are induced by the parasitic microsporidians to develop huge cells, known as xenomas, which are full of spores. Given their large size, what should be true of the xenomas?

A) The parasite must endow the xenoma with some way to overcome its unfavorable surface area-to-volume ratio.
B) The xenoma must obtain mitochondria to survive.
C) The xenoma must gain a cell wall; otherwise, it will lyse.
D) The xenoma acts as a prison, of sorts, to keep the spores from escaping and infecting other organisms.

Answer 22

A) The parasite must endow the xenoma with some way to overcome its unfavorable surface area-to-volume ratio.

Question 23

What are the sporangia of the bread mold Rhizopus?

A) asexual structures that produce haploid spores
B) asexual structures that produce diploid spores
C) sexual structures that produce haploid spores
D) sexual structures that produce diploid spores

Answer 23

A) asexual structures that produce haploid spores

Question 24

Which of these paired fungal structures are structurally and functionally most alike?

A) conidia and basidiocarps
B) sporangia and hyphae
C) soredia and gills
D) haustoria and arbuscules
E) zoospores and mycelia

Answer 24

D) haustoria and arbuscules

Question 25

You are given an organism to identify. It has a fruiting body that contains many structures with eight haploid spores lined up in a row. What kind of a fungus is this?

A) zygomycete
B) ascomycete
C) deuteromycete
D) chytrid
E) basidiomycete

Answer 25

B) ascomycete

Question 26

Which of the following has the least affiliation with all of the others?

A) Glomeromycota
B) mycorrhizae
C) lichens
D) arbuscules
E) mutualistic fungi

Answer 26

C) lichens

Question 27

Arrange the following from largest to smallest:

1. ascospore
2. ascocarp
3. ascomycete
4. ascus

A) 3 → 4 → 2 → 1
B) 3 → 2 → 4 → 1
C) 3 → 4 → 1 → 2
D) 2 → 3 → 4 → 1
E) 2 → 4 → 1 → 3

Answer 27

B) 3 → 2 → 4 → 1

Question 28

Arrange the following from largest to smallest, assuming that they all come from the same fungus.

1. basidiocarp
2. basidium
3. basidiospore
4. mycelium
5. gill

A) 4 → 5 → 1→ 2 → 3
B) 5 → 1 → 4 → 2 → 3
C) 5 → 1 → 4 → 3 → 2
D) 5 → 1 → 3 → 2 → 4
E) 4 → 1 → 5 → 2 → 3

Answer 28

E) 4 → 1 → 5 → 2 → 3

Question 29

Among sac fungi, which of these correctly distinguishes ascospores from conidia?

A) Ascospores are diploid, whereas conidia are haploid.
B) Ascospores are produced only by meiosis, whereas conidia are produced only by mitosis.
C) Ascospores have undergone genetic recombination during their production, whereas conidia have not.
D) Ascospores are larger, whereas conidia are smaller.
E) Ascospores will germinate into haploid hyphae, whereas conidia will germinate into diploid hyphae.

Answer 29

C) Ascospores have undergone genetic recombination during their production, whereas conidia have not.

Question 30

A fungal spore germinates, giving rise to a mycelium that grows outward into the soil surrounding the site where the spore originally landed. Which of the following accounts for the fungal movement, as described here?

A) karyogamy
B) mycelial flagella
C) alternation of generations
D) breezes distributing spores
E) cytoplasmic streaming in hyphae

Answer 30

E) cytoplasmic streaming in hyphae

Question 31

In what structures do both Penicillium and Aspergillus produce asexual spores?

A) asci
B) zygosporangia
C) rhizoids
D) gametangia
E) conidiophores

Answer 31

E) conidiophores

Question 32

Chemicals, secreted by soil fungi, that inhibit the growth of bacteria are known as:

A) antibodies.
B) aflatoxins.
C) hallucinogens.
D) antigens.
E) antibiotics.

Answer 32

E) antibiotics.

Question 33

Lichens are symbiotic associations of fungi and

A) mosses.
B) cyanobacteria.
C) green algae.
D) Three of these responses are correct.
E) Two of these responses are correct.

Answer 33

E) Two of these responses are correct.

Question 34

In both lichens and mycorrhizae, what does the fungal partner provide to its photosynthetic partner?

A) carbohydrates
B) fixed nitrogen
C) antibiotics
D) water and minerals
E) protection from harmful UV

Answer 34

D) water and minerals

Question 35

Which of the following best describes the physical relationship of the partners involved in lichens?

A) Fungal cells are enclosed within algal cells.
B) Lichen cells are enclosed within fungal cells.
C) Photosynthetic cells are surrounded by fungal hyphae.
D) The fungi grow on rocks and trees and are covered by algae.
E) Algal cells and fungal cells mix together without any apparent structure.

Answer 35

C) Photosynthetic cells are surrounded by fungal hyphae.

Question 36

If haustoria from the fungal partner were to appear within the photosynthetic partner of a lichen, and if the growth rate of the photosynthetic partner consequently slowed substantially, then this would support the claim that

A) algae and cyanobacteria are autotrophic.
B) lichens are not purely mutualistic relationships.
C) algae require maximal contact with the fungal partner in order to grow at optimal rates.
D) fungi get all of the nutrition they need via the “leakiness” of photosynthetic partners.
E) soredia are asexual reproductive structures combining both the fungal and photosynthetic partners.

Answer 36

B) lichens are not purely mutualistic relationships.

Question 37

When pathogenic fungi are found growing on the roots of grape vines, grape farmers sometimes respond by covering the ground around their vines with plastic sheeting and pumping a gaseous fungicide into the soil. The most important concern of grape farmers who engage in this practice should be that the

A) fungicide might also kill the native yeasts residing on the surfaces of the grapes.
B) lichens growing on the vines’ branches are not harmed.
C) fungicide might also kill mycorrhizae.
D) sheeting is transparent so that photosynthesis can continue.

Answer 37

C) fungicide might also kill mycorrhizae.

Question 38

Which of the following terms refers to symbiotic relationships that involve fungi living between the cells in plant leaves?

A) pathogens
B) endosymbioses
C) endophytes
D) lichens
E) mycorrhizae

Answer 38

C) endophytes

Question 39

If Penicillium typically secretes penicillin without disturbing the lichen relationship in which it is engaged, then what must have been true about its partner?

A) It should have lacked peptidoglycan in its cell wall.
B) It was probably a red alga.
C) It was probably a member of the domain Bacteria.
D) It was probably a heterotrophic prokaryote.
E) It was probably infected by bacteriophage.

Answer 39

A) It should have lacked peptidoglycan in its cell wall.

Question 40

Sexual reproduction has never been observed among the fungi that produce the blue-green marbling of blue cheeses. What is true of these fungi and others that do not have a sexual stage?

A) They are currently classified among the ascomycetes.
B) They do not form heterokaryons.
C) Their spores are probably produced by mitosis.
D) Three of these responses are correct.
E) Two of these responses are correct.

Answer 40

C) Their spores are probably produced by mitosis.

Question 41

Both fungus-derived antibiotics and hallucinogens used by humans probably evolved in fungi as a means to:

A) reduce competition for nutrients.
B) help humanity survive.
C) promote their ingestion of foodstuffs.
D) eliminate other fungi.
E) discourage animal predators.

Answer 41

A) reduce competition for nutrients.

Question 42

A billionaire buys a sterile volcanic island that recently emerged from the sea. To speed the arrival of conditions necessary for plant growth, the billionaire might be advised to aerially sow what over the island?

A) basidiospores
B) spores of ectomycorrhizae
C) soredia
D) yeasts
E) leaves (as food for fungus-farming ants)

Answer 42

C) soredia

Question 43

Mycorrhizae are to the roots of vascular plants as endophytes are to vascular plants’

A) leaf mesophyll.
B) stem apical meristems.
C) root apical meristems
D) xylem.
E) waxy cuticle.

Answer 43

A) leaf mesophyll.

Question 44

Which of the following conditions is caused by a fungus that is accidentally consumed along with rye flour?

A) ergotism
B) athlete's foot
C) ringworm
D) candidiasis (Candida yeast infection)
E) coccidioidomycosis

Answer 44

A) ergotism

Question 45

Orchid seeds are tiny, with virtually no endosperm and with miniscule cotyledons. If such seeds are deposited in a dark, moist environment, then which of the following represents the most likely means by which fungi might assist in seed germination, given what the seeds lack?

A) by transferring some chloroplasts to the embryo in each seed
B) by providing the seeds with water and minerals
C) by providing the embryos with some of the organic nutrients they have absorbed
D) by strengthening the seed coat that surrounds each seed

Answer 45

C) by providing the embryos with some of the organic nutrients they have absorbed