Bio 212 Exam 3 Questions and Verified
Answers
Identify at least three human diseases caused by fungi. - CORRECT ANSWERS -A few examples
are athlete's foot, vaginitis, diaper rash, ringworm, pneumonia, and thrush.
Explain why it can be beneficial to inoculate seeds of crop plants with mycorrhizal fungi. -
CORRECT ANSWERS -Plants that grow in association with mycorrhizal fungi are likely to grow
faster and more robustly than plants without the fungi
Explain how fungi help connect two major parts of the cycle: carbon fixation and carbon
release. - CORRECT ANSWERS -By digesting large carbon-containing compounds (such as lignin
and cellulose)由atwould otherwise be tied up in dead trees and other organisms, fungi produce
small organic molecules and release C02 through cellular respiration. This C02 is later absorbed
by plants and fixed during photosynthesis into sugars (and later processed back into lignin,
cellulose, and other large organic compounds).
Identify the four types of sexual reproductive structures observed in fungi. - CORRECT
ANSWERS -Swimming spores and gametes, zygosporangia, basidia, and asci
Explain how mold on a single piece of fruit can easily spread to nearby fruit - CORRECT
ANSWERS -Many types of mold consist of large numbers of conidia (asexual spores). These
spores are released and can easily start to grow on nearby fruit
Evaluate whether morels (ascomycetes) or bread molds (zygomycetes) are more closely related
to mushrooms (basidiomycetes). - CORRECT ANSWERS -Ascomycetes and basidiomycetes share
a recent common ancestor. Therefore, ascomycetes are more closely related to basidiomycetes
than they are to zygomycetes
PROCESS OF SCIENCE What do these labeled nutrient " experiments tell you that you didn't
already know from experiments like that shown in Figure 29.2, where plants are grown with
and without mycorrhizae? - CORRECT ANSWERS -
Describe evidence that mutualism occurs in EMF - CORRECT ANSWERS -When birch tree
seedlings are
grown in the presence and in the absence of EMF, individuals denied their normal EMF cannot
acquire sufficient nitrogen and phosphorus. The EMF acquire sugars from the birch. Therefore,
both organisms benefit.
Explain the role of spores in fungal reproduction - CORRECT ANSWERS -Spores are haploid cells
that can
, be distributed long distances. When environmental conditions are favorable, they can
germinate and grow into fungal hyphae
Compare and contrast what happens inside a
zygosporangium, a basidium, and an ascus. - CORRECT ANSWERS -Meiosis and the production
of haploid spores occur in each of these structures.
In a zygosporangium, meiosis occurs in a multinucleate cell; in basidia and asci, there is a single
diploid nucleus. In asci, meiosis is followed by one round of mitosis.
1. Explain the role of the polar tube in microsporidial infections. - CORRECT ANSWERS -The
polar tube can penetrate. the cell membrane of a host cell and provide a passage way for the
microsporidian to enter the host cell.
Explain how Glomeromycota can be beneficial to plants - CORRECT ANSWERS -Members of the
Glomeromycota form mycorrhizal relationships with plants. As a result, the plants can acquire
more nitrogen and phosphorus than they are able to without the fungi
Explain whether or not budding produces genetic variation in yeasts. - CORRECT ANSWERS -
Budding produces new yeast cells by mitosis. Therefore, the newly formed yeast cells are
genetically identical and budding does not lead to genetic variation.
The mycelial growth habit leads to a body with a high surface-area- to-volume ratio. Why is this
important?
a. Mycelia have a large surface area for absorption.
b. The hyphae that make up mycelia are long, thin tubes.
c. Most hyphae are broken up into compartments by walls called septa, although some exist as
single, gigantic cells.
d. Hyphae can infiltrate living or dead tissues. - CORRECT ANSWERS -a. mycelia have a large
surface area for absorption
Evaluate the following statements about mushrooms. Select True or
False for each statement.
T/F A diploid zygote is formed when a male spore fertilizes a female spore.
T/F Haploid spores are formed by meiosis in basidia.
T/F A mushroom is a reproductive structure that consists largely of dikaryotic cells.
T/F Mushrooms are part of the group that also includes bracket fungi, boletes, puffballs, and
stinkhorns. - CORRECT ANSWERS -F ( Spores grow into fungal hyphae; they are not involved in
fertilization, and they are not designated as male and female.), T, T, T.
Answers
Identify at least three human diseases caused by fungi. - CORRECT ANSWERS -A few examples
are athlete's foot, vaginitis, diaper rash, ringworm, pneumonia, and thrush.
Explain why it can be beneficial to inoculate seeds of crop plants with mycorrhizal fungi. -
CORRECT ANSWERS -Plants that grow in association with mycorrhizal fungi are likely to grow
faster and more robustly than plants without the fungi
Explain how fungi help connect two major parts of the cycle: carbon fixation and carbon
release. - CORRECT ANSWERS -By digesting large carbon-containing compounds (such as lignin
and cellulose)由atwould otherwise be tied up in dead trees and other organisms, fungi produce
small organic molecules and release C02 through cellular respiration. This C02 is later absorbed
by plants and fixed during photosynthesis into sugars (and later processed back into lignin,
cellulose, and other large organic compounds).
Identify the four types of sexual reproductive structures observed in fungi. - CORRECT
ANSWERS -Swimming spores and gametes, zygosporangia, basidia, and asci
Explain how mold on a single piece of fruit can easily spread to nearby fruit - CORRECT
ANSWERS -Many types of mold consist of large numbers of conidia (asexual spores). These
spores are released and can easily start to grow on nearby fruit
Evaluate whether morels (ascomycetes) or bread molds (zygomycetes) are more closely related
to mushrooms (basidiomycetes). - CORRECT ANSWERS -Ascomycetes and basidiomycetes share
a recent common ancestor. Therefore, ascomycetes are more closely related to basidiomycetes
than they are to zygomycetes
PROCESS OF SCIENCE What do these labeled nutrient " experiments tell you that you didn't
already know from experiments like that shown in Figure 29.2, where plants are grown with
and without mycorrhizae? - CORRECT ANSWERS -
Describe evidence that mutualism occurs in EMF - CORRECT ANSWERS -When birch tree
seedlings are
grown in the presence and in the absence of EMF, individuals denied their normal EMF cannot
acquire sufficient nitrogen and phosphorus. The EMF acquire sugars from the birch. Therefore,
both organisms benefit.
Explain the role of spores in fungal reproduction - CORRECT ANSWERS -Spores are haploid cells
that can
, be distributed long distances. When environmental conditions are favorable, they can
germinate and grow into fungal hyphae
Compare and contrast what happens inside a
zygosporangium, a basidium, and an ascus. - CORRECT ANSWERS -Meiosis and the production
of haploid spores occur in each of these structures.
In a zygosporangium, meiosis occurs in a multinucleate cell; in basidia and asci, there is a single
diploid nucleus. In asci, meiosis is followed by one round of mitosis.
1. Explain the role of the polar tube in microsporidial infections. - CORRECT ANSWERS -The
polar tube can penetrate. the cell membrane of a host cell and provide a passage way for the
microsporidian to enter the host cell.
Explain how Glomeromycota can be beneficial to plants - CORRECT ANSWERS -Members of the
Glomeromycota form mycorrhizal relationships with plants. As a result, the plants can acquire
more nitrogen and phosphorus than they are able to without the fungi
Explain whether or not budding produces genetic variation in yeasts. - CORRECT ANSWERS -
Budding produces new yeast cells by mitosis. Therefore, the newly formed yeast cells are
genetically identical and budding does not lead to genetic variation.
The mycelial growth habit leads to a body with a high surface-area- to-volume ratio. Why is this
important?
a. Mycelia have a large surface area for absorption.
b. The hyphae that make up mycelia are long, thin tubes.
c. Most hyphae are broken up into compartments by walls called septa, although some exist as
single, gigantic cells.
d. Hyphae can infiltrate living or dead tissues. - CORRECT ANSWERS -a. mycelia have a large
surface area for absorption
Evaluate the following statements about mushrooms. Select True or
False for each statement.
T/F A diploid zygote is formed when a male spore fertilizes a female spore.
T/F Haploid spores are formed by meiosis in basidia.
T/F A mushroom is a reproductive structure that consists largely of dikaryotic cells.
T/F Mushrooms are part of the group that also includes bracket fungi, boletes, puffballs, and
stinkhorns. - CORRECT ANSWERS -F ( Spores grow into fungal hyphae; they are not involved in
fertilization, and they are not designated as male and female.), T, T, T.
