Bio 212 Exam 3 Questions And Answers With Verified
Study Solutions
Identify at least three human diseases caused by fungi. ANS 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. ANS 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.
ANS 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. ANS Swimming spores
and gametes, zygosporangia, basidia, and asci
Explain how mold on a single piece of fruit can easily spread to nearby fruit ANS 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). ANS 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? ANS
Describe evidence that mutualism occurs in EMF ANS 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 ANS 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. ANS 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. ANS 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 ANS 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. ANS 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. ANS a. mycelia have a large surface area for
absorption
Evaluate the following statements about mushrooms. Select True or
False for each statement.
Study Solutions
Identify at least three human diseases caused by fungi. ANS 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. ANS 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.
ANS 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. ANS Swimming spores
and gametes, zygosporangia, basidia, and asci
Explain how mold on a single piece of fruit can easily spread to nearby fruit ANS 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). ANS 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? ANS
Describe evidence that mutualism occurs in EMF ANS 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 ANS 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. ANS 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. ANS 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 ANS 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. ANS 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. ANS a. mycelia have a large surface area for
absorption
Evaluate the following statements about mushrooms. Select True or
False for each statement.
