Question 1

Use the following information to answer the question.
Suzanne Simard and colleagues knew that the same mycorrhizal fungal species could colonize multiple types of trees. They wondered if the same fungal individual would colonize different trees, forming an underground network that potentially could transport carbon and nutrients from one tree to another (S. Simard et al. 1997. Net transfer of carbon between mycorrhizal tree species in the field. Nature 388:579-82).
Pots containing seedlings of three different tree species were set up and grown under natural conditions for three years (Fig.A). Two of the three species (Douglas fir, birch) could form ectomycorrhizal connections with the same fungal species, but the third species (cedar) could not form an ectomycorrhizal connection with the fungal species. In some of the pots, the researchers placed airtight bags over the Douglas fir and birch seedlings and injected carbon dioxide made from carbon-13 into the bags with the Douglas fir and carbon dioxide made from carbon-14 into the bags with the birch. (¹³C and ¹⁴C are different isotopes of carbon that can be detected and measured by researchers.) As the seedlings photosynthesized, the carbon dioxide was converted into sugars that could be tracked and measured by the researchers. The researchers measured whether the sugars in each plant contained only the carbon isotope that was in the air of their plastic bag or also the carbon isotope from the air around the other plant.

Figure A
Based on the idea that fungi have pores between their cell walls that allow cytoplasm to move from one end of the mycelium to the other, which of the following hypotheses is the most plausible?
A) If a single mycorrhizal fungus formed symbiotic associations with more than one tree, carbon could travel from one plant to another.
B) Parasitic fungi steal nutrients from their hosts.
C) Predatory fungi capture their prey by encircling them with hyphae, and the flowing of the cytoplasm through the pores helps the hyphae to move around the prey.
D) Fungi function as part of the global carbon cycle, not only by converting carbon from one form to another, but by physically moving it from one location to another.

Accepted Answer

The hypothesis that a single mycorrhizal fungus forming symbiotic associations with more than one tree could potentially allow for carbon to be transported from one plant to another is the most plausible based on the experiment described in the text. The injected isotopes of carbon were detectable in the sugars of both Douglas fir and birch, indicating that carbon was indeed moving between the two trees via the shared fungal species. The other choices are not related to the experiment and do not reflect the main idea presented in the passage.

Question 2

Use the following information to answer the question.
Suzanne Simard and colleagues knew that the same mycorrhizal fungal species could colonize multiple types of trees. They wondered if the same fungal individual would colonize different trees, forming an underground network that potentially could transport carbon and nutrients from one tree to another (S. Simard et al. 1997. Net transfer of carbon between mycorrhizal tree species in the field. Nature 388:579-82).
Pots containing seedlings of three different tree species were set up and grown under natural conditions for three years (Fig.A). Two of the three species (Douglas fir, birch) could form ectomycorrhizal connections with the same fungal species, but the third species (cedar) could not form an ectomycorrhizal connection with the fungal species. In some of the pots, the researchers placed airtight bags over the Douglas fir and birch seedlings and injected carbon dioxide made from carbon-13 into the bags with the Douglas fir and carbon dioxide made from carbon-14 into the bags with the birch. (¹³C and ¹⁴C are different isotopes of carbon that can be detected and measured by researchers.) As the seedlings photosynthesized, the carbon dioxide was converted into sugars that could be tracked and measured by the researchers. The researchers measured whether the sugars in each plant contained only the carbon isotope that was in the air of their plastic bag or also the carbon isotope from the air around the other plant.

Figure A
Referring to Simard et al. (1997), which design element is the control in this experiment and why?
A) the bags over the seedlings to contain the different types of carbon dioxide
B) the fact that all the seedlings are different species
C) the cedar seedling, because it is not bagged
D) the cedar seedling, because it does not form ectomycorrhizal connections with the tested fungus

Accepted Answer

The cedar seedling serves as the control in this experiment because it does not form ectomycorrhizal connections with the tested fungus, and thus carbon transfer between the cedar and the other two species would not occur even if the bags were present.

Question 3

Use the following information to answer the question.
There is much discussion in the media about protecting biodiversity. But does biodiversity really matter? Canadian and Swiss researchers wanted to know if the diversity of arbuscular mycorrhizal fungi (AMF) was important to the productivity of grasslands (M.G.A. van der Heijden, J. N. Klironomos, M. Ursic, P. Moutoglis, R. Streitwolf-Engel, T. Boler, A. Wiemken, and I. R. Sanders. 1998. Mycorrhizal fungal diversity determines plant biodiversity, ecosystem variability, and productivity. Nature 396:69-72). Specifically, they wanted to know if it mattered which specific AMF species were present, or just that some type of AMF was present. They grew various plants in combination with one of four AMF species (A, B, C, and D), no AMF species (O), or all four AMF species together (A + B + C + D); and they measured plant growth under each set of conditions. All plant species were grown in each plot, so they always competed with each other, with the only difference being which AMF species were present.
On the graphs, the x-axis labels indicate the number and identity of AMF species (bar 0 = no fungi; bars A - D = individual AMF species; bar A + B + C + D = all AMF species together). The y-axis indicates the amount (grams) of plant biomass for the species shown in italics above each graph.

A) Carex flacca (graph a)
B) Lotus corniculatus (graph b)
C) Sanguisorba officinalis (graph c)
D) Centaurium erythrea (graph d)

Accepted Answer

A

Question 4

Use the following information to answer the question.
Suzanne Simard and colleagues knew that the same mycorrhizal fungal species could colonize multiple types of trees. They wondered if the same fungal individual would colonize different trees, forming an underground network that potentially could transport carbon and nutrients from one tree to another (S. Simard et al. 1997. Net transfer of carbon between mycorrhizal tree species in the field. Nature 388:579-82).
Pots containing seedlings of three different tree species were set up and grown under natural conditions for three years (Fig.A). Two of the three species (Douglas fir, birch) could form ectomycorrhizal connections with the same fungal species, but the third species (cedar) could not form an ectomycorrhizal connection with the fungal species. In some of the pots, the researchers placed airtight bags over the Douglas fir and birch seedlings and injected carbon dioxide made from carbon-13 into the bags with the Douglas fir and carbon dioxide made from carbon-14 into the bags with the birch. (¹³C and ¹⁴C are different isotopes of carbon that can be detected and measured by researchers.) As the seedlings photosynthesized, the carbon dioxide was converted into sugars that could be tracked and measured by the researchers. The researchers measured whether the sugars in each plant contained only the carbon isotope that was in the air of their plastic bag or also the carbon isotope from the air around the other plant.

Figure A
Which of the following results would support Simard et al.'s (1997) hypothesis that fungi can move carbon from one plant to another? [Hypothesis: Sugars made by one plant during photosynthesis can travel through a mycorrhizal fungus and be incorporated into the tissues of another plant.]
A) Carbon-14 is found in the birch seedling's tissues and carbon-13 in the Douglas fir.
B) Carbon-14 is found in the Douglas fir seedling's tissues and carbon-13 in the birch.
C) Either carbon-13 or carbon-14 is found in the fungal tissues.
D) Either carbon-13 or carbon-14 is found in the cedar seedling's tissues.

Accepted Answer

The experiment involved injecting different isotopes of carbon (¹³C and ¹⁴C) into the bags with the seedlings of different tree species. If the mycorrhizal fungus network can transport carbon from one plant to another, then the sugars made by one plant should be detected in the tissues of another plant that shares the same fungal individual. In this case, if carbon-14 is found in the Douglas fir seedling's tissues and carbon-13 in the birch, it would suggest that the carbon made by the birch has been transferred through the fungus to the Douglas fir. The other choices do not directly support the hypothesis or are not relevant to the experimental design.

Question 5

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) fungal enzymes
C) increased oxygen levels
D) larger bacterial populations

Accepted Answer

When a mycelium infiltrates an unexploited source of dead organic matter, it secretes fungal enzymes that break down the complex organic molecules into simpler nutrients that can be absorbed and used by the mycelium. This is known as external digestion. Fungal haustoria are specialized structures that allow fungi to obtain nutrients from living cells of other organisms, not dead organic matter. Increased oxygen levels and larger bacterial populations are not directly related to the process of mycelium infiltrating dead organic matter.

Question 6

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

Accepted Answer

Mycorrhizae form a mutually beneficial relationship with grape vines where they provide the plant with nutrients and in return receive sugars. If the fungicide also kills off these beneficial fungi, it may have a negative impact on the health and growth of the grape vines. A and B are not the most important concern, while D is not relevant to the issue at hand.

Question 7

Use the following information to answer the question.
Suzanne Simard and colleagues knew that the same mycorrhizal fungal species could colonize multiple types of trees. They wondered if the same fungal individual would colonize different trees, forming an underground network that potentially could transport carbon and nutrients from one tree to another (S. Simard et al. 1997. Net transfer of carbon between mycorrhizal tree species in the field. Nature 388:579-82).
Pots containing seedlings of three different tree species were set up and grown under natural conditions for three years (Fig.A). Two of the three species (Douglas fir, birch) could form ectomycorrhizal connections with the same fungal species, but the third species (cedar) could not form an ectomycorrhizal connection with the fungal species. In some of the pots, the researchers placed airtight bags over the Douglas fir and birch seedlings and injected carbon dioxide made from carbon-13 into the bags with the Douglas fir and carbon dioxide made from carbon-14 into the bags with the birch. (¹³C and ¹⁴C are different isotopes of carbon that can be detected and measured by researchers.) As the seedlings photosynthesized, the carbon dioxide was converted into sugars that could be tracked and measured by the researchers. The researchers measured whether the sugars in each plant contained only the carbon isotope that was in the air of their plastic bag or also the carbon isotope from the air around the other plant.

Simard et al. (1997) further hypothesized that if reciprocal transfer did occur, it would be a source-sink relationship driven by photosynthetic rates. That is, if one seedling is in full sun and the other in deep shade, there will be a net movement of carbon from the seedling in full sun to the one in deep shade. If a shade were placed over the birch seedlings and the cedar, and the Douglas fir was left in full sun, what result could Simard and colleagues expect?
A) More ¹³C would be found in the birch than ¹⁴C in the Douglas fir.
B) The amounts of ¹³C and ¹⁴C would be equal in the Douglas fir and in the birch.
C) The most ¹³C would be found in the cedar.
D) The most ¹⁴C would be found in the cedar.

Accepted Answer

If a shade is placed over the birch and cedar, and the Douglas fir is left in full sun, then the Douglas fir should receive more sunlight and have higher photosynthetic rates than the shaded birch and cedar. Therefore, there would be a net movement of carbon from the Douglas fir to the shaded birch and cedar. Since carbon-13 was injected into the bags with the Douglas fir and carbon-14 was injected into the bags with the birch, there will be more carbon-13 detected in the birch than carbon-14 detected in the Douglas fir. Thus, the researchers would expect to find more ¹³C in the birch than ¹⁴C in the Douglas fir.

Question 8

There is much discussion in the media about protecting biodiversity. But does biodiversity really matter?
Canadian and Swiss researchers wanted to know if the diversity of arbuscular mycorrhizal fungi (AMF) was important to the productivity of grasslands (M.G.A. van der Heijden, J. N. Klironomos, M. Ursic, P. Moutoglis, R. Streitwolf-Engel, T. Boler, A. Wiemken, and I. R. Sanders. 1998. Mycorrhizal fungal diversity determines plant biodiversity, ecosystem variability, and productivity. Nature 396:69-72). Specifically, they wanted to know if it mattered which specific AMF species were present, or just that some type of AMF was present. They grew various plants in combination with one of four AMF species (A, B, C, and D), no AMF species (O), or all four AMF species together (A + B + C + D); and they measured plant growth under each set of conditions. All plant species were grown in each plot, so they always competed with each other, with the only difference being which AMF species were present.
On the graphs, the x-axis labels indicate the number and identity of AMF species (bar 0 = no fungi; bars A - D = individual AMF species; bar A + B + C + D = all AMF species together). The y-axis indicates the amount (grams) of plant biomass for the species shown in italics above each graph.

Examine the effect of AMF species on Sanguisorba officinalis. Which of the following conclusions can be correctly drawn from the data?
A) Growth is best with AMF species D.
B) Growth is best with AMF species A.
C) Growth is best with a mixture of AMF species.
D) AMF presence had no effect on S. officinalis growth.

Accepted Answer

The answer of There is much discussion in the media...

Question 9

Use the following information to answer the question.
Canadian and Swiss researchers wanted to know if the diversity of arbuscular mycorrhizal fungi (AMF) was important to the productivity of grasslands (M.G.A. van der Heijden, J. N. Klironomos, M. Ursic, P. Moutoglis, R. Streitwolf-Engel, T. Boler, A. Wiemken, and I. R. Sanders. 1998. Mycorrhizal fungal diversity determines plant biodiversity, ecosystem variability, and productivity. Nature 396:69-72). Specifically, they wanted to know if it mattered which specific AMF species were present, or just that some type of AMF was present. They grew various plants in combination with one of four AMF species (A, B, C, and D), no AMF species (O), or all four AMF species together (A + B + C + D); and they measured plant growth under each set of conditions. All plant species were grown in each plot, so they always competed with each other with the only difference being which AMF species were present.
On the graphs, the x-axis labels indicate the number and identity of AMF species (bar 0 = no fungi; bars A - D = individual AMF species; bar A + B + C + D = all AMF species together). The y-axis indicates the amount (grams) of plant biomass for the species shown in italics above each graph. Graph e is the total biomass (grams) of all 11 plant species combined; graph f is the biomass of Bromus erectus plants only, separated from the total.

What is the major difference between Bromus erectus (graph f) and the other plant species (graphs a-d) included in the study?
A) Bromus erectus grows best with a diversity of fungal partners.
B) Bromus erectus is unaffected by AMF diversity.
C) Bromus erectus does not form mycorrhizal associations.
D) Bromus erectus produces very little biomass regardless of AMF.

Accepted Answer

The answer of Use the following information to answer the...

Question 10

Some fungal species live in plants and can kill herbivores that feed on the plant. What type of relationship does this fungus have with its host?
A) parasitic
B) mutualistic
C) commensal
D) predatory

Accepted Answer

Fungi that live in plants and kill herbivores are examples of mutualistic relationships. The fungus benefits from a nutrient source provided by the plant, and in exchange, the plant benefits from herbivore control.

Question 11

Use the following information to answer the question.
There is much discussion in the media about protecting biodiversity. But does biodiversity really matter? Canadian and Swiss researchers wanted to know if the diversity of arbuscular mycorrhizal fungi (AMF) was important to the productivity of grasslands (M.G.A. van der Heijden, J. N. Klironomos, M. Ursic, P. Moutoglis, R. Streitwolf-Engel, T. Boler, A. Wiemken, and I. R. Sanders. 1998. Mycorrhizal fungal diversity determines plant biodiversity, ecosystem variability, and productivity. Nature 396:69-72). Specifically, they wanted to know if it mattered which specific AMF species were present, or just that some type of AMF was present. They grew various plants in combination with one of four AMF species (A, B, C, and D), no AMF species (O), or all four AMF species together (A + B + C + D); and they measured plant growth under each set of conditions. All plant species were grown in each plot, so they always competed with each other, with the only difference being which AMF species were present.
On the graphs, the x-axis labels indicate the number and identity of AMF species (bar 0 = no fungi; bars A - D = individual AMF species; bar A + B + C + D = all AMF species together). The y-axis indicates the amount (grams) of plant biomass for the species shown in italics above each graph.

Based on the van der Heijden et al. (1998) graphs in the figure, which of the following is the best description of the data supporting the idea that a plant species did not form mycorrhizae with a fungus? Its biomass is greatest when ________.
A) no AMF are present
B) AMF species A is present
C) AMF species B is present
D) AMF species C is present

Accepted Answer

The graph shows that for the plant species Festuca ovina, its biomass is highest when no AMF species are present (bar 0). This suggests that this plant species did not form mycorrhizae with any of the tested AMF species.

Question 12

There is much discussion in the media about protecting biodiversity. But does biodiversity really matter?
Canadian and Swiss researchers wanted to know if the diversity of arbuscular mycorrhizal fungi (AMF) was important to the productivity of grasslands (M.G.A. van der Heijden, J. N. Klironomos, M. Ursic, P. Moutoglis, R. Streitwolf-Engel, T. Boler, A. Wiemken, and I. R. Sanders. 1998. Mycorrhizal fungal diversity determines plant biodiversity, ecosystem variability, and productivity. Nature 396:69-72). Specifically, they wanted to know if it mattered which specific AMF species were present, or just that some type of AMF was present. They grew various plants in combination with one of four AMF species (A, B, C, and D), no AMF species (O), or all four AMF species together (A + B + C + D); and they measured plant growth under each set of conditions. All plant species were grown in each plot, so they always competed with each other, with the only difference being which AMF species were present.
On the graphs, the x-axis labels indicate the number and identity of AMF species (bar 0 = no fungi; bars A - D = individual AMF species; bar A + B + C + D = all AMF species together). The y-axis indicates the amount (grams) of plant biomass for the species shown in italics above each graph

Examine all four graphs and choose the plant species that grows best with a combination of AMF species.
A) Carex flacca (graph a)
B) Lotus corniculatus (graph b)
C) Sanguisorba officinalis (graph c)
D) Centaurium erythrea (graph d)

Accepted Answer

In graph b, the plant species Lotus corniculatus shows the greatest increase in biomass when grown with all four AMF species together (A + B + C + D) compared to when no AMF species are present (bar 0). This suggests that the specific combination of AMF species is important for the growth and productivity of this plant species, and therefore biodiversity of AMF species may be important for ecosystem productivity.

Question 13

Use the following information to answer the question.
Suzanne Simard and colleagues knew that the same mycorrhizal fungal species could colonize multiple types of trees. They wondered if the same fungal individual would colonize different trees, forming an underground network that potentially could transport carbon and nutrients from one tree to another (S. Simard et al. 1997. Net transfer of carbon between mycorrhizal tree species in the field. Nature 388:579-82).
Pots containing seedlings of three different tree species were set up and grown under natural conditions for three years (Fig.A). Two of the three species (Douglas fir, birch) could form ectomycorrhizal connections with the same fungal species, but the third species (cedar) could not form an ectomycorrhizal connection with the fungal species. In some of the pots, the researchers placed airtight bags over the Douglas fir and birch seedlings and injected carbon dioxide made from carbon-13 into the bags with the Douglas fir and carbon dioxide made from carbon-14 into the bags with the birch. (¹³C and ¹⁴C are different isotopes of carbon that can be detected and measured by researchers.) As the seedlings photosynthesized, the carbon dioxide was converted into sugars that could be tracked and measured by the researchers. The researchers measured whether the sugars in each plant contained only the carbon isotope that was in the air of their plastic bag or also the carbon isotope from the air around the other plant.

Figure A
Referring to Simard et al. (1997), what is the result that would most strongly refute their hypothesis? [Hypothesis: Sugars made by one plant during photosynthesis can travel through a mycorrhizal fungus and be incorporated into the tissues of another plant.]
A) No movement: Carbon-14 is found in the birch seedling's tissues and carbon-13 in the Douglas fir.
B) Reciprocal exchange: Carbon-14 is found in the Douglas fir seedling's tissues and carbon-13 in the birch.
C) Either carbon-13 or carbon-14 is found in the fungal tissues.
D) Either carbon-13 or carbon-14 is found in the cedar seedling's tissues.

Accepted Answer

If either carbon-13 or carbon-14 is found in the cedar seedling's tissues, it would refute the hypothesis that the mycorrhizal network is transporting sugars between plants, since cedar cannot form ectomycorrhizal connections with the fungal species being used in the experiment. The transfer of labeled carbon between Douglas fir and birch could support the hypothesis (option B), as could the detection of either isotope in the fungal tissues (option C).

Question 14

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) breezes distributing spores
D) cytoplasmic streaming in hyphae

Accepted Answer

Cytoplasmic streaming in hyphae allows for movement and extension of the mycelium. Mycelial flagella do not exist in fungi. Breezes may distribute spores, but they do not account for the movement described in this scenario. Karyogamy is the process of nuclear fusion during sexual reproduction and does not relate to the movement of the mycelium.

Question 15

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) the potential to inhabit almost all terrestrial habitats
C) the increased probability of contact between different 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 the fungi to effectively decompose organic matter and obtain nutrients from their surroundings. This gives them a significant adaptive advantage over other organisms.

Question 16

Use the following information to answer the question.
In the United States and Canada, bats use one of two strategies to survive winter. They either migrate south, or they hibernate. Recently, those that hibernate seem to have come under attack by a fungus, Geomyces destructans (Gd), an attack that is occurring from Missouri to New England, Canada, and even the state of Washington. Many infected bats have a delicate, white filamentous mat on their muzzles, which is referred to as white-nose syndrome (WNS). The fungus invades the bat tissues, causes discomfort, and awakens the bat from its hibernation. The bat fidgets and wastes calories, using up its stored fat. The bat then behaves abnormally, leaving its cave during daytime in winter to search for food. Their food, primarily insects, is scarce during the winter, and the bats ultimately starve to death. Since 2006, it is estimated that over six million bats have perished from WNS.
The Gd mat on the fur of the bats should be expected to consist of ________.
A) hyphae
B) haustoria
C) yeasts
D) basidia

Accepted Answer

The delicate, white filamentous mat on the muzzles of infected bats is caused by the fungus Geomyces destructans (Gd), which invades bat tissues. This type of fungal growth is characteristic of hyphae, which are thread-like structures that make up the body of a fungus. Therefore, the Gd mat on the fur of the bats should be expected to consist of hyphae. Haustoria are specialized hyphae that penetrate host tissues for nutrient uptake, yeasts are single-celled fungi, and basidia are structures found in the fruiting body of certain fungi that produce spores. None of these structures are relevant to the Gd infection of bats.

Question 17

What do fungi and arthropods have in common?
A) The haploid state is dominant in both groups.
B) Both groups are predominantly autotrophs that produce their own food.
C) Both groups use chitin for support.
D) Both groups have cell walls.

Accepted Answer

Both fungi and arthropods use chitin for support. Fungi have cell walls made of chitin, while arthropods have exoskeletons made of chitin.

Question 18

Fungi have an extremely high surface-to-volume ratio. What is the advantage of this characteristic to an organism that gets most of its nutrition through absorption?
A) The high ratio allows for more material to be acquired from the surroundings and transported through the cell membrane.
B) The lower volume prevents the cells from drying out too quickly, which can interfere with absorption.
C) This high ratio creates more room inside the cells for additional organelles involved in absorption.
D) This high ratio means that fungi have a thick, fleshy structure that allows the fungi to store more of the food it absorbs.

Accepted Answer

The high surface-to-volume ratio allows for more material to be acquired from the surroundings and transported through the cell membrane, increasing the efficiency of absorption.

Question 19

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) flowering plants
B) protists
C) prokaryotes
D) grasses

Accepted Answer

Fungi play a major role in decomposition of organic matter in the environment. If they were to suddenly die, the prokaryotes would benefit most, as they would be able to compete for the resources left behind by the fungi. Other organisms such as flowering plants and grasses may also benefit to some extent, but prokaryotes are the primary decomposers in most environments and would therefore be the greatest beneficiaries. Protists may also play a role in decomposition, but they are not as well-equipped as prokaryotes to break down complex organic matter.

Question 20

Use the following information to answer the question.
There is much discussion in the media about protecting biodiversity. But does biodiversity really matter? Canadian and Swiss researchers wanted to know if the diversity of arbuscular mycorrhizal fungi (AMF) was important to the productivity of grasslands (M.G.A. van der Heijden, J. N. Klironomos, M. Ursic, P. Moutoglis, R. Streitwolf-Engel, T. Boler, A. Wiemken, and I. R. Sanders. 1998. Mycorrhizal fungal diversity determines plant biodiversity, ecosystem variability, and productivity. Nature 396:69-72). Specifically, they wanted to know if it mattered which specific AMF species were present, or just that some type of AMF was present. They grew various plants in combination with one of four AMF species (A, B, C, and D), no AMF species (O), or all four AMF species together (A + B + C + D); and they measured plant growth under each set of conditions. All plant species were grown in each plot, so they always competed with each other, with the only difference being which AMF species were present.
On the graphs, the x-axis labels indicate the number and identity of AMF species (bar 0 = no fungi; bars A - D = individual AMF species; bar A + B + C + D = all AMF species together). The y-axis indicates the amount (grams) of plant biomass for the species shown in italics above each graph.

In graph b in the figure, which of the following best explains the data given about Lotus corniculatus?
A) This plant grows best when AMF taxa A or C is present.
B) Lotus corniculatus does not form mycorrhizal associations.
C) Mycorrhizal fungi parasitize the plant's roots when they are present, reducing its growth.
D) This plant forms multiple AMF associations, growing best with increased fungal diversity.

Accepted Answer

The answer of Use the following information to answer the...

Quiz 31: Fungi

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

Some fungal species live in plants and can kill herbivores that feed on the plant. What type of relationship does this fungus have with its host?

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?

The adaptive advantage associated with the filamentous nature of fungal mycelia is primarily related to ________.

What do fungi and arthropods have in common?

Fungi have an extremely high surface-to-volume ratio. What is the advantage of this characteristic to an organism that gets most of its nutrition through absorption?

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?