The Evolution of Plant and Fungal Diversity Answer Key 47-71 + Bonus

47) A mushroom A) is composed of many threadlike filaments called mycorrhizae. B) is specialized to obtain most of the nutrients for the fungal mycelium. C) is an independent stage in the alternation of generations of the fungal life cycle. D) is an aboveground reproductive structure connected to a mycelium. Answer: D 48) Fungi contact and absorb food through the ________, a branching network of ________. A) mycelium; hyphae B) hyphae; mycelia C) mycorrhiza; mushrooms D) mushroom; hyphae Answer: A 49) Which of the following structures is an essential part of most fungal reproductive systems? A) gametangia B) cellulose C) seeds D) spores Answer: D 50) The heterokaryotic phase of a fungal life cycle is A) a stage in which the hyphae contain only one type of haploid nucleus. B) a stage in which hyphae contain two genetically different haploid nuclei. C) a stage in which hyphae contain two genetically different diploid nuclei. D) a triploid stage formed by the fusion of a diploid nucleus with the haploid nucleus of a compatible hypha. Answer: B 51) Which type of reproduction is typical in molds? A) sexual reproduction through mating of two diploid parent mycelia B) sexual reproduction through fusion of two haploid parent mycelia and subsequent production of haploid spores C) asexual reproduction through budding D) asexual reproduction through the production of spores Answer: D 52) The last common ancestor of animals and fungi was probably ________, like the spores of ________ fungi. A) flagellated; chytrid B) flagellated; mold C) multicellular; chytrid D) nonflagellated; yeast Answer: A 53) About 80% of plants have mycorrhizae linking them to A) chytrids. B) glomeromycetes. C) ascomycetes. D) basidiomycetes. Answer: B 54) Most familiar types of mushrooms, along with puffballs and shelf fungi, are A) chytrids. B) ascomycetes. C) zygomycetes. D) basidiomycetes. Answer: D 55) If fungi of the genus Cordyceps are ingested by insects, fruiting bodies will form and erupt through the bodies of the insects. Cordyceps are an example of A) symbiosis. B) parasitic fungi. C) lichens. D) mycorrhizae. Answer: B 56) Which of the following occurs in the sexual reproduction phase of the fungus life cycle? A) Hyphae of two different mating types fuse. B) Diploid nuclei form, undergo meiosis, and produce haploid spores. C) Heterokaryotic cells separate to re-create the original haploid hyphae. D) Spores germinate and form a haploid mycelium. Answer: B 57) Fungal diseases common in ________ include ________ and ________. A) plants; smuts; rusts B) animals; smuts; chytrids C) plants; ringworm; coccidioidomycosis D) humans; rusts; vaginal yeast Answer: A 58) Gangrene, hallucinations, temporary insanity, and even death can result when humans consume grain infested with A) corn smut. B) chytrids. C) coccidioidomycosis. D) ergots. Answer: D 59) An experimental forest ecosystem is enclosed in a sealed greenhouse. The entire ecosystem, including the air and soil, is treated with an extremely potent fungicide that kills all fungal life stages including spores. What will probably happen next? A) Tree growth will increase because the dead fungi will act as a fertilizer. B) Plants will enjoy a long-term increase in growth and survival because of the removal of fungal pathogens. C) Dead organic matter will accumulate on the forest floor; plant growth will decline because of a lack of nutrients and the loss of mycorrhizal partners. D) A few animals will go extinct due to loss of their fungal food sources, but otherwise the forest will be largely unchanged. Answer: C 60) Which of the following statements regarding fungi is false? A) Fungi are important decomposers in ecosystems. B) Fungi can only break down plant material. C) The distinctive flavor of certain cheeses is due to fungi. D) The first antibiotic discovered came from a fungus. Answer: B 61) What kind of entity is a lichen? A) an association between a fungus and a brown alga B) an association between a multicellular protist related to the brown algae and a bacterium C) an association between a fungus and cyanobacteria or green algae D) an association between a bryophyte and a fungus Answer: C 62) You enjoy learning about history by studying gravestones throughout North America. You notice that gravestones from 1900 and earlier usually host many types of lichens. But in one cemetery, lichens are entirely absent, even from old gravestones. Given what is known about lichens, the cemetery without lichens probably A) has an unusually dry climate. B) is subject to extremely cold winter temperatures. C) gets a great deal of rain, which favors the growth of competing bacteria. D) is close to a source of air pollution. Answer: D 63) The plant genus Pinus reaches optimal growth when it grows with the fungal genus Suillusis. The ________ of the fungus give Pinus water and mineral nutrients, while Pinus gives the fungus sugars and organic macromolecules. Pinus and Suillusis have a ________ relationship. A) hyphae; symbiotic B) spores; symbiotic C) chitin; eukaryotic D) fruit; endothermic Answer: A 64) Mycorrhizal fungi are sometimes purposely introduced to new areas of land that are used for growing plants for commercial uses (e.g., landscaping, crop production, timber production). What would be the benefit of doing this? A) The fungi absorb toxic pesticides from the ground. B) The fungi help facilitate horticulture, agriculture, and forestry. C) The fungi promote the evolution of new fungus species. D) The fungi prevent competitive plant species from growing. Answer: B 65) Different kinds of mycorrhizae occur in different ecosystems. For example, as you walk up a mountain, you might find one type of mycorrhizae in lower regions and a second, different type of mycorrhizae in higher regions. Why are there mycorrhizae specific to certain ecosystems? A) Mycorrhizae are adapted to the altitude. B) Mycorrhizae are adapted to the type of slope of the land. C) Mycorrhizae tend to colonize all levels of the mountain. D) Mycorrhizae are adapted to the type of soil and the type of vegetation present. Answer: D 66) Suppose you take two young cuttings of a house plant. You cut the roots off of one cutting and then place both cuttings in a jar of red dye. After 20 minutes, the roots, stem, and leaves of the cutting with roots have turned pink. The cutting without roots has not changed color at all. Why has the cutting without roots remained a normal, green color? A) Cutting the roots has damaged the xylem, so the plant can no longer take up water. B) Cutting the roots has damaged the phloem, so the plant can no longer take up water. C) Cutting the roots has damaged the apical meristem, so the plant can no longer take up water. D) Cutting the roots has damaged the sporangia, so the plant can no longer take up water. Answer: A 67) A maple tree's seeds occur in pairs that are enclosed and attached to flat "wings" that are made of a papery tissue. The wings' shape allows them to spin in the air as they fall from the tree; this unusual motion has earned them the nickname "helicopter seeds." Maple tree seeds are most successful when they are dispersed by ________. A) wind B) water C) animal feces D) bird feces Answer: A 68) Tomato seeds are often consumed by birds or other organisms and then dispersed through their feces. However, when tomatoes rot on the vine, organisms may not consume them. How would tomato seeds likely disperse in this situation? A) When the tomato rots, it drops to the ground and the seeds fall in the soil. B) Summer rains carry the seeds to a new area. C) Windy conditions carry the seeds to a new area. D) The tomato disperses its seeds as spores. Answer: A 69) It is difficult to tell if a mushroom sticking out of the ground is a living, reproducing organism. Which of the following would be the best evidence to demonstrate that mushrooms are living, reproducing organisms? A) flagellated sperm B) pollen C) lignin D) spore production and dispersal Answer: D 70) A comet orchid has creamy white-colored flowers and a characteristic "tail" that contains the flower's nectar. This orchid does not emit a scent during daylight hours but is aromatic at night. The comet orchid is most likely pollinated by A) windy nighttime conditions. B) pollen traveling on animal fur. C) a nocturnal pollinator. D) moisture from cool evenings. Answer: C 71) Which of the following statements is true? A) Gymnosperms have seeds that are not enclosed in a protective casing, while angiosperms have flowers that produce seeds with a protective casing. B) Gymnosperms have flowers that produce seeds with a protective casing, while angiosperms have seeds that are not enclosed in a protective casing. C) Gymnosperms lack true roots and leaves, while angiosperms lack lignin cell walls. D) Gymnosperms lack seeds, while angiosperms have flowers that produce seeds with a protective casing. Answer: A 17.2 Art Questions 1) According to this figure, at what time in the evolutionary history of plants did vascular systems likely first evolve? A) 475 mya B) 460 mya C) 425 mya D) 360 mya Answer: C 2) Which part of this figure represents the anther? A) structure A B) structure B C) structure C D) structure D Answer: A 17.3 Scenario Questions After reading the paragraphs below, answer the questions that follow. Scientists believe that a shift from pollination by insects to pollination by birds occurred several times over the course of angiosperm evolution. Two researchers designed an experiment to investigate how these shifts might evolve using two species of monkey flower (Mimulus spp.). M. lewisii has violet-pink flowers and is pollinated by bumblebees. M. cardinalis has orange-red flowers and is pollinated by hummingbirds. The researchers switched flower-color genes between the two species. As a result of the gene transfer, they produced a variation of M. cardinalis with dark pink flowers (instead of the original orange-red) and a variation of M. lewisiis with orange flowers (instead of the original violet-pink). Plants of both genetically altered varieties were placed in their original habitats and observed. The genetically altered variety of M. cardinalis was visited by bumblebees 74 times more often than plants with the original color flowers. The genetically altered variety of M. lewisii was visited by hummingbirds 68 times more often than plants with the original color flowers. 1) Based on the results of this study, you can conclude that A) petal color won't contribute to speciation, since pollinators will select familiar plant species regardless of petal color. B) gene mutations that affect petal color will also affect nectar production. C) gene mutations affecting petal color can contribute to speciation through a shift in pollinator species. D) flower color does not appear to be an important factor in the speciation of flowering angiosperms. Answer: C 2) The evolution of easily modified flower colors that can make plants attractive to animals was an important factor in angiosperm evolution because A) plants have no way to cross-pollinate without the intervention of animals. B) animals are more effective at delivering pollen to other flowers than is the wind. C) flower color attracts animals that can disperse the seeds of the plant. D) successful evolution requires interactions between plants and animals. Answer: B After reading the statement below, answer the questions that follow. A leaf with a higher density of stomata can take up more CO2 and release more water than a leaf with a lower density of stomata. 3) Consider two plant types: 1. Plants that grow in arid (dry) environments 2. Plants that grow in moist (e.g., wetland) environments Which plant would you expect to have more stomata, and why? A) the first type, because plants in arid environments need to release as much water as possible B) the first type, because plants in arid environments need to conserve as much water as possible C) the second type, because plants in moist environments need to conserve as much water as possible D) The two types should have equal numbers of stomata, because they both need to maintain the same water balance in their cells. Answer: B 4) The stomata found on fossil plants can be a reliable way to measure past carbon dioxide levels. Normally, fossil plants with high density of stomata indicate ________ carbon dioxide levels and fossil plants with only a few stomata indicate ________ carbon dioxide levels. A) low; high B) high; high C) low; low D) high; low Answer: D After reading the paragraph below, answer the questions that follow. Crop plants can have higher densities of stomata on the underside of their leaves than on the surfaces of their leaves. Some scientists hypothesize that that the evolution of this adaptation enhanced the ability of these plants to regulate the rate of CO2 uptake for each surface. 5) Suppose you wanted to test this hypothesis using sunflower plants. Which of the following would be the best procedure regarding the groups you use in your experiment? A) Choose two equal-size groups of sunflower plants. One would be the experimental group and one would be the control group. B) Choose equal-size groups of sunflower plants and zinnia plants. The sunflower plants would be the experimental group and the zinnia plants would be the control group. C) Choose two groups of sunflower plants. The experimental group would have twice as many plants as the control group. D) Choose two groups of sunflower plants. The experimental group would have half as many plants as the control group. Answer: A 6) You designed and performed an experiment that measured CO2 gas exchange levels at the upper side of a sunflower leaf (fewer stomata) and the bottom side of a sunflower leaf (greater stomata). After collecting and analyzing your data, you conclude that there was not a significant difference in CO2 gas exchange between the two sides of the leaf. Which of the following possibly explains this finding? A) The difference in the density of stomata on the two leaf surfaces is not likely due to an adaptation related to gas exchange regulation. B) The difference in the density of stomata on the two leaf surfaces is likely due to specific mechanisms that sunflowers use to disperse their seeds. C) The difference in the density of stomata on the two leaf surfaces is likely due to mycorrhizal associations with other plants. D) The difference in the density of stomata on the two leaf surfaces is likely due to different pollination needs for each surface. Answer: A