Chp.31 Flashcards

Fungi are __________, which use enzymes to break down a large variety of complex molecules into smaller organize compounds

___________ are mutually beneficial relationships between fungi and plant roots.

Fungi propagate themselves by producing vast numbers of ______, either sexually or asexually.

Fungal nuclei are normally __________, with the exception of transient diploid stages formed during the sexual life cycles.

Fungi sexual reproduction requires the fusion of _______ from different mating types.

Fungi use sexual signaling molecules called __________ (like insects) to communicate their mating type.

__________ is the union of two parent mycelia.

_________ is the fusion of nuclei from parent fungi, thus making nuclei diploid.

Other fungi that can reproduce asexually are ________ (unicellular fungi), which inhabit moist environments.

many molds and yeasts have no known sexual stage. mycologists have traditionally called these ___________, or imperfect fungi.

_________ are unicellular parasites of animals and protists.

__________ (phylum Chytridiomycota) are found in freshwater and terrestrial habitats; they can be unicellular and colony-forming.

The __________ (phylum Zygomycota) exhibit great diversity of life histories. they are resistant to freezing and drying and can survive unfavorable conditions.

The __________ were once considered zygomycetes. They are now classified in a separate clade. they form arbuscular mycorrhizae: hyphae extend into plant roots, branch forming arbuscules.

__________ are mutually beneficial relationships between fungi and plant roots.

__________ fungi form sheaths of hyphae over a root and also grow into the extracellular spaces of the root cortex.

__________ _________ fungi extend hyphae through the cell walls of root cells and into tubes formed by invagination of the root cell membrane.

_________ live in marine, freshwater, and terrestrial habitats. The phylum is defined by production of sexual spores in saclike asci, usually contained in fruiting bodies called ascocarps. commonly called sac fungi.

__________ include mushrooms, puffballs, shelf fungi, rusts, smuts. the phylum is defined by a club-like structure called a basidium, a transient diploid stage in the life cycle. also called club fungi.

Fungi are efficient _________; they perform essential recycling of chemical elements between the living and nonliving world.

a ________ is a symbiotic association between a photosynthetic microorganism and a fungus in which millions of photosynthetic cells are held in a mass of fungal hyphae.

The general term for a fungal infection in animals and humans is ________.

Some fungi are used to produce antibiotics for the treatment of bacterial infections, for example the ascomycete __________.

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.

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.

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

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

The vegetative (nutritionally active) bodies of most fungi are
A) composed of hyphae.
B) referred to as a mycelium.
C) usually underground.
D) A, B, and C are correct.
E) A and B are correct.

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.

Immediately after karyogamy occurs, which term applies?
A) plasmogamy
B) heterokaryotic
C) dikaryotic
D) diploid

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

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

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.

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.

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

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.

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

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.

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

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

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

Which of the following has the least affiliation with all of the others?
A) Glomeromycota
B) mycorrhizae
C) lichens
D) arbuscules
E) mutualistic fungi

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.

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

In what structures do both Penicillium and Aspergillus produce asexual spores?
A) asci
B) zygosporangia
C) rhizoids
D) gametangia
E) conidiophores

Chemicals, secreted by soil fungi, that inhibit the growth of bacteria are known as
A) antibodies.
B) aflatoxins.
C) hallucinogens.
D) antigens.
E) antibiotics.

Lichens are symbiotic associations of fungi and
A) mosses.
B) cyanobacteria.
C) green algae.
D) all are correct.
E) B and C are correct

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

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.

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

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.

Mycorrhizae are to the roots of vascular plants as endophytes are to the ________ vascular plants.
A) leaf mesophyll.
B) stem apical meristems.
C) root apical meristems
D) xylem.
E) waxy cuticle.

All fungi share which of the following characteristics?
A) symbiotic
B) heterotrophic
C) flagellated
D) pathogenic
E) act as decomposers

Which feature seen in chytrids supports the hypothesis that they diverged earliest in fungal evolution?
A) the absence of chitin within the cell wall
B) coenocytic hyphae
C) flagellated spores
D) formation of resistant zygosporangia
E) parasitic lifestyle

Which of the following cells or structures are associated with asexual reproduction in fungi?
A) ascospores
B) basidiospores
C) zygosporangia
D) conidiophores
E) ascocarps

The photosynthetic symbiont of a lichen is often
A) a moss.
B) a green alga.
C) a brown alga.
D) an ascomycete.
E) a small vascular plant.

Among the organisms listed here, which are thought to be the closest relatives of fungi?
A) animals
B) vascular plants
C) mosses
D) brown algae
E) slime molds

The adaptive advantage associated with the filamentous nature of fungal mycelia is primarily related to
A) the ability to form haustoria and parasitize other organisms.
B) avoiding sexual reproduction until the environment changes.
C) the potential to inhabit almost all terrestrial habitats.
D) the increased probability of contact between different mating types.
E) an extensive surface area well suited for invasive growth and absorptive nutrition.