Ch 29

43) Many amphibian populations have been decimated by a parasitic fungus classified as a member of the ________.

A) Chytridiomycota

39) You observe the gametes of a fungal species under the microscope and realize that they resemble animal sperm. To which of the following groups does the fungus belong?

A) Chytrids

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

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

15) 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?

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

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

A) a zygote enclosed in a tough outer coat

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

A) animals

40) The sporangia of the bread mold Rhizopus are ________.

A) asexual structures that produce haploid spores

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

A) flagellated spores

26) 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 ________.

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

4) Fungi that absorb nutrients from decaying plant matter are called ________.

A) saprobes

16) 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?

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

28) 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?

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

42) Microsporidians are considered parasitic because of the ability to penetrate their host cells using ________.

B) a polar tube

30) 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?

B) arbuscular mycorrhizal fungi

23) 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?

B) ascomycete

24) 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?

B) by flagella

44) Lichens are symbiotic associations of fungi and ________.

B) cyanobacteria or algae

5) All fungi are ________.

B) heterotrophic

31) 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?

B) mutualistic

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

B) pores in septa

47) Some fungi have been instrumental in the development of human culture, including __________ in the Phylum ________ as they have been in use for hundreds of years in producing beer and bread.

B) yeasts; Ascomycota

46) ________ form ectomycorrhizal relationships with temperate forest trees while ________ form arbuscular (endomycorrhizal) relationships with plants in grasslands and tropical forests.

C) Basidiomycetes; glomeromycetes

10) 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?

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

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

C) 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.

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

C) Photosynthetic cells are surrounded by fungal hyphae.

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

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

37) Which of the following terms refers to symbiotic relationships involving fungi living between the cells in plant leaves?

C) endophytes

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

C) fungal enzymes

3) 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 ________.

C) fungicide might also kill mycorrhizae

20) Fungi with hyphae ________.

C) have cell walls that consist mainly of cellulose microfibrils

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

D) Fungi secrete extracellular enzymes that can break down large molecules.

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

D) The cell walls of fungi are made of chitin.

6) What is the major distinguishing characteristic of fungi?

D) nutrient acquisition via external digestion

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

D) plasmogamy

38) In most fungi, karyogamy does NOT immediately follow plasmogamy, which consequently ________.

D) results in heterokaryotic or potentially even dikaryotic cells

41) In both lichens and mycorrhizae, what does the fungal partner provide to its photosynthetic partner?

D) water and minerals

9) The vegetative (nutritionally active) bodies of most fungi are ________. I. composed of hyphae II. referred to as a mycelium III. usually underground

E) I, II, and III

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

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

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

E) antibiotics

8) Long, branching fungal filaments are called ________.

E) hyphae