Question 1

Which of the following statements accurately describes our current understanding of the phylogeny of fungi as represented in the figure? 
A) the chytrids are a basal taxon
B) zygoomycetes are more closely related to ascomycetes than they are to glomeromycetes
C) basidiomycetes are more closely related to zygomycetes than they are to ascomycetes
D) glomeromycetes are a basal taxon

Accepted Answer

The answer of Which of the following statements accurately describes...

Question 2

In which of the following human mycoses should one expect to find a growth pattern most similar to that of the mycelium that produces a fairy ring?
A) skin mycoses
B) coccidiomycosis (lung infection)
C) systemic (blood-borne) Candida infection
D) infection of lymphatic vessels

Accepted Answer

Skin mycoses involve superficial fungal infections on the skin, where the fungi grow in a pattern similar to the radial expansion of a fairy ring, as they spread outward from a central point.

Question 3

The closest relatives of fungi are thought to be the ________.
A) animals
B) vascular plants
C) mosses
D) slime molds

Accepted Answer

Fungi are more closely related to animals than to plants, mosses, or slime molds. This relationship is based on molecular evidence, including DNA sequences, that shows fungi and animals share a more recent common ancestor with each other than with plants or other organisms.

Question 4

If you wanted to use fungi to improve the environment, which of the following research goals would make the most sense?
A) Discover the lignin-digesting enzymes of fungi, and use them to digest plant tissues left over from food-crop residues to reduce landfill waste.
B) Discover the enzymes that the fungal partner in lichens uses to break down rock so that large rock expanses can be turned into agricultural lands.
C) Discover the enzymes that fungi use to break down plant matter and use them to increase decomposition rates in order to slow global warming.
D) Develop a strain of fungus that produces enzymes that absorb oxygen and will help slow global warming.

Accepted Answer

Fungi have enzymes that can break down lignin, a complex organic polymer in plant cell walls. Using these enzymes to digest plant residues can reduce landfill waste, making this a practical environmental improvement.

Question 5

The most important adaptive advantage associated with the filamentous nature of fungal mycelia is ________.
A) the ability to form haustoria and parasitize other organisms
B) the potential to inhabit almost all terrestrial habitats
C) the increased chance of contact between mating types
D) an extensive surface area well suited for invasive growth and absorptive nutrition

Accepted Answer

The filamentous nature of fungal mycelia provides an extensive surface area that is well suited for invasive growth and absorptive nutrition, allowing fungi to efficiently absorb nutrients from their environment.

Question 6

Mycorrhizae are often found associated with the roots of vascular plants. Where are fungal endophytes typically found in vascular plants?
A) leaf mesophyll
B) stem apical meristems
C) root apical meristems
D) xylem

Accepted Answer

Fungal endophytes are typically found within the leaf mesophyll of vascular plants, where they live intercellularly or intracellularly, often providing benefits such as increased resistance to pathogens and stress.

Question 7

Fungi produce many compounds that humans use medicinally. Which of the following statements best describes the evolution of these compounds in fungi?
A) Humans used artificial selection to develop fungi that produced specific compounds.
B) The presence of the compounds in the fungi were accidentally produced and have no function.
C) The compounds probably provide a benefit to the fungi.
D) The compounds are produced as a result of sexual reproduction and recombination.

Accepted Answer

The compounds produced by fungi likely evolved because they offer some advantage to the fungi, such as protection against predators, parasites, or competition from other microorganisms. This evolutionary perspective suggests that these compounds serve a functional role in the survival and fitness of fungi.

Question 8

Which of the following statements describes the relationship between a fungus and a photosynthetic microorganism in a lichen?
A) neither organism derives any benefit from the relationship
B) the fungus provides the photosynthetic microorganism a suitable environment for growth
C) the fungus fixes nitrogen for the photosynthetic microorganism
D) the photosynthetic microorganism helps the fungus retain minerals

Accepted Answer

Lichens are symbiotic associations where the fungus provides a structure and environment that protects the photosynthetic microorganisms (such as algae or cyanobacteria) from harsh conditions, enabling them to photosynthesize and produce nutrients.

Question 9

All fungi are ________.
A) symbiotic
B) heterotrophic
C) flagellated
D) decomposers

Accepted Answer

Fungi are heterotrophic, meaning they cannot manufacture their own food and must obtain their nutrients from organic substances.

Question 10

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) Fungi grow on rocks and trees and are covered by algae.

Accepted Answer

Lichens are symbiotic associations where the photosynthetic partner, which can be algae or cyanobacteria, is surrounded by fungal hyphae. This arrangement allows the fungus to provide protection and structure, while the photosynthetic partner produces nutrients through photosynthesis.

Question 11

A billionaire buys a sterile volcanic island that recently emerged from the sea. Seeding the island with which of the following would most likely accelerate the development of conditions that would support plant growth?
A) basidiospores
B) spores of ectomycorrhizae
C) lichens
D) yeasts

Accepted Answer

Lichens are symbiotic associations between fungi and algae (or cyanobacteria) that can colonize bare rock and start the soil formation process by breaking down the rock and accumulating organic matter. This makes them crucial for initiating the development of conditions that support plant growth on a new volcanic island.

Question 12

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

Accepted Answer

Conidiophores are specialized fungal structures that produce conidia, which are asexual spores, thus playing a role in asexual reproduction in fungi.

Question 13

Truffles are the fruiting bodies of certain fungi whose mycelium grows below ground. The truffle is also underground and can be detected by many mammals, which eat the truffle and expel the spores with their feces. Which of the following statements is likely accurate with respect to this interaction?
A) The truffle spores are probably wind dispersed.
B) Truffles produce an odor that mammals can detect and find attractive.
C) Truffles probably produce toxins that can harm the mammals that eat them.
D) Truffle fruiting bodies are important in decomposition of wood.

Accepted Answer

Truffles produce a strong, distinctive odor that attracts mammals. These animals then eat the truffles and disperse the spores through their feces, aiding in the reproduction of the fungi. This mutualistic relationship benefits both the truffles, by spreading their spores, and the mammals, by providing them with a food source.

Question 14

Orchid seeds are tiny, with virtually no endosperm and with miniscule cotyledons. If orchid 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?
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 the fungi have absorbed
D) by strengthening the seed coat that surrounds each seed

Accepted Answer

Orchid seeds lack substantial stored nutrients, which are essential for germination and initial growth. Fungi can form symbiotic relationships with orchid seeds, where the fungi provide organic nutrients to the seeds. This mutualistic interaction is crucial for the germination of many orchid species, as the fungi supply the necessary carbon and energy sources to the seedlings.

Question 15

Fungi interact with many organisms in mutualistic ways. Which of the following involves a fungus that is mutualistic with another organism?
A) a fungus and a protozoan that live together as a lichen
B) a fungus that is raised by ants on leaves that the ants collect from trees and shrubs
C) a fungus that lives inside plant roots and produces toxins that kill neighboring plants
D) a fungus that produces penicillin that is used by humans to kill infectious bacteria

Accepted Answer

Fungi and ants have a mutualistic relationship where ants cultivate fungi by providing them with leaves, and in return, the fungi serve as a food source for the ants.

Question 16

Use the following information to answer the question.
Rose-picker's disease is caused by the yeast Sporothrix schenkii that if introduced into the human body can assume a hyphal morphology and grow along the interiors of lymphatic vessels until they reach a lymph node.
Lymph nodes are important for the immune system because many white blood cells (phagocytes and lymphocytes) reside there.
Given that a successful infection by S. schenkii damages lymph nodes themselves, which of the following is most probable?
A) The hyphae secrete antibiotics, which increases the ability of the infected human to tolerate the fungus.
B) The fungal conversion from yeast to hyphal morphology allows such fast growth that the body's defenses are at least temporarily overwhelmed.
C) Defensive cells of humans cannot detect foreign cells that are covered with cell walls composed of cellulose.
D) Given that most fungal pathogens attack plants, human defenses are simply not adapted to seek out and destroy fungi.

Accepted Answer

The fungal conversion from yeast to hyphal morphology enables rapid growth, potentially overwhelming the body's defenses temporarily. This rapid expansion can make it difficult for the immune system to respond effectively before significant damage occurs.

Quiz 31: Introduction to Fungi

Which of the following statements accurately describes our current understanding of the phylogeny of fungi as represented in the figure?

In which of the following human mycoses should one expect to find a growth pattern most similar to that of the mycelium that produces a fairy ring?

The closest relatives of fungi are thought to be the ________.

If you wanted to use fungi to improve the environment, which of the following research goals would make the most sense?

The most important adaptive advantage associated with the filamentous nature of fungal mycelia is ________.

Mycorrhizae are often found associated with the roots of vascular plants. Where are fungal endophytes typically found in vascular plants?

Fungi produce many compounds that humans use medicinally. Which of the following statements best describes the evolution of these compounds in fungi?

Which of the following statements describes the relationship between a fungus and a photosynthetic microorganism in a lichen?

All fungi are ________.

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

A billionaire buys a sterile volcanic island that recently emerged from the sea. Seeding the island with which of the following would most likely accelerate the development of conditions that would support plant growth?

Which of the following cells or structures are associated with asexual reproduction in fungi?

Orchid seeds are tiny, with virtually no endosperm and with miniscule cotyledons. If orchid 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?

Fungi interact with many organisms in mutualistic ways. Which of the following involves a fungus that is mutualistic with another organism?