Fungi

The vegetative (nutritionally active) bodies of most fungi are _____.

1, 2, and 3

You are a forester charged with increasing productivity in a South American forest newly planted with pines from Oregon. You believe that the southern forest lacks the fungal diversity needed by the North American pines, and that this lack of fungi is affecting the pines' productivity, but you have no evidence to support your ideas. To count how many fungal species were present in the Oregon forest, which methodology would you choose?

Do direct sequencing on representative soil samples from across the forest.

Why is it more difficult to treat fungal infections than bacterial infections in humans?

Fungal and animal cells and proteins are similar. Thus, drugs that disrupt fungal cell or protein function may also disrupt human cell or protein function.

Which of the following is an important role for fungi in the carbon cycle?

Fungi release fixed carbon back to the environment for other plants and photosynthetic organisms to utilize.

Why are mycorrhizal fungi superior to plants at acquiring mineral nutrition from the soil?

Fungi secrete extracellular enzymes that can break down large molecules.

Based on the idea that fungi have pores between their cell walls, which allow cytoplasm to move from one end of the mycelium to the other, which of the following hypotheses is the most plausible?

If a single mycorrhizal fungus formed symbiotic associations with more than one tree, carbon could travel from one plant to another.

It has been hypothesized that fungi and plants have a mutualistic relationship because plants make sugars available for the fungi's use. What is the best evidence in support of this hypothesis?

Radioactively labeled sugars produced by plants eventually show up in the fungi with which they are associated.

Which of these fungal features supports the phylogenetic conclusion that fungi are more closely related to animals than plants?

The cell walls of fungi are made of chitin.

Why is it important that ectomycorrhizal fungi (EMF) have peptidase enzymes?

These enzymes are needed to release nitrogen from dead plant material in colder environments.

Basidiomycetes are the only fungal group capable of synthesizing lignin peroxidase. What advantage does this group of fungi have over other fungi because of this capability?

This fungal group can break down the tough lignin, which cannot be harnessed for energy, to get to the more useful cellulose.

In graph (b) in the figure above, which of the following best explains the data given about Lotus corniculatus?

This plant forms multiple AMF associations, growing best with increased fungal diversity.

Predict what you would see if you were looking at a new species of Zygomycetes.

a zygote enclosed in a tough outer coat

What is the major distinguishing characteristic of fungi?

absorbing nutrients

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

an extensive surface area well suited for invasive growth and absorptive nutrition

Among the organisms listed here, which are thought to be the closest relatives of fungi?

animals

Chemicals, secreted by soil fungi, which inhibit the growth of bacteria, are known as _____.

antibiotics

What group of fungi has the ability to penetrate its host's cell wall, thus increasing the efficiency with which materials are passed from fungus to host?

arbuscular mycorrhizal fungi

Fungi with hyphae _____.

are adapted for rapid directional growth to new food sources

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?

ascomycete

Apart from direct amphibian-to-amphibian contact, what is the most likely means by which the zoospores spread from one free-living amphibian to another?

by flagella

Which of the following characteristics is unique to chytrids compared to other groups of fungi?

flagellated spores

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

fungal enzymes

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 _____.

fungicide might also kill mycorrhizae

All fungi are _____.

heterotrophic

Long, branching fungal filaments are called _____.

hyphae

Some fungal species can kill herbivores while feeding off of sugars from its plant host. What type of relationship does this fungus have with its host?

mutualistic

It has been hypothesized that fungi and plants have a mutualistic relationship because fungi provide critical nitrogen for the plants' use. How do we know this happens? In experiments using radioactively labeled _____.

nitrogen, plants acquired more radioactive nitrogen when they were associated with fungi

Based on the van der Heijden et al. (1998) graphs in the figure above, 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 _____.

no AMF are present

At which stage of a basidiomycete's life cycle would reproduction be halted if an enzyme that prevented the fusion of hyphae was introduced?

plasmogamy

In septate fungi, what structures allow cytoplasmic streaming to distribute needed nutrients, synthesized compounds, and organelles throughout the hyphae?

pores in septa

Fungi that absorb nutrients from decaying plant matter are called _____.

saprobes