1. Embryonic shoots located at the tips of stems are called, while those located in the angle between leaves and stems are known as. A. nodes; internodes B. axillary buds; terminal buds C. terminal buds; axillary buds D. axillary buds; lateral buds E. bud scales; bud scale scars 2. Lenticels function to: A. protect undeveloped embryonic shoots. B. allow the diffusion of oxygen into woody stems. C. support leaves and flowers. D. absorb water and dissolved nutrient minerals. E. anchor a plant in the ground. 3. The single layer of meristematic cells located between xylem and phloem is referred to as the: A. apical meristem. B. collenchyma. C. cork cambium. D. vascular cambium. E. pith. 4. Secondary growth occurs as a result of the activity of which two lateral meristems? A. vascular cambium and cork cambium B. apical meristem and cork cambium C. primary meristem and secondary meristem D. periderm and cork cambium E. apical meristem and vascular cambium 5. Cork cambium and the tissues it produces are collectively known as: A. periderm. B. epidermis. C. xylem. D. pith. E. cortex. 6. Xylem transports water and dissolved nutrient minerals in which direction? A. upward B. downward C. inward laterally D. outward laterally E. both upward and downward 7. Water moves from a region of water potential to a region of water potential. A. more positive; less positive B. less positive; more positive C. less negative; more negative D. more negative; less negative E. more negative; zero 36-1
8. Water is capable of rising to the tops of the tallest trees due to all of the following except: A. the hydrogen bonds among water molecules. B. the cohesiveness of water molecules. C. the adhesion of water to the walls of xylem cells. D. the evaporative pull of transpiration. E. root pressure. 9. Before being loaded into the phloem for translocation, the carbohydrates produced during photosynthesis must be converted into which molecule? A. glucose B. fructose C. maltose D. sucrose E. galactose 10. Sugar is translocated in phloem from a source, or an area of, to a sink, or an area of. A. low sugar concentration; high sugar concentration B. high sugar concentration; low sugar concentration C. positive water potential; negative water potential D. negative water potential; positive water potential E. low pressure; equally low pressure 11. Guttation, a phenomenon during which liquid water is forced out through special openings in the leaves, results from. A. water pressure B. transpiration pull C. osmotic pressure D. root pressure E. All of these. 12. According to the pressure-flow hypothesis: A. water moves from an area of positive water potential to an area of negative water potential. B. the evaporative pull of transpiration produces tension at the top of the plant. C. the flow of sugar is driven by a hydrostatic pressure gradient produced by water entering the phloem. D. pressure is created by the movement of water into the roots from the soil. E. the column of water pulled up through the plant is unbroken due to cohesive and adhesive properties. 13. One function of roots is: A. absorption of dissolved sugars for use by the plant. B. photosynthesis. C. storage of food reserves. D. sexual reproduction. E. production of micronutrients. 36-2
14. The difference between taproot and fibrous root systems is that a taproot system: A. consists of many roots of the same size, while a fibrous root system has one main root with lateral roots. B. consists of one main root with lateral roots, while a fibrous root system has many roots of the same size. C. is characteristic of most monocots, while a fibrous root system is usually found in eudicots. D. can be modified for storage, while a fibrous root system cannot. E. is considered adventitious, while a fibrous root system is not. 15. Which of the following statements about root cap is FALSE? A. It protects the delicate root apical meristem B. It secretes lubricating polysaccharides C. It orients the root that it grows downward D. It loses cells during root growth. E. It absorbs nutrients. 16. Which of the following statements about root hairs is true? A. They are short lived tubular extensions of epidermal cells. B. They are continually formed in the area of cell maturation. C. They are quite numerous. D. They greatly increase the absorptive capacity of roots. E. All these are characters of root hairs. 17. Which layer of cells controls the movement of nutrient minerals entering the xylem in the root s interior? A. endodermis B. Casparian strip C. epidermis D. cortex E. periderm 18. The symplast: A. greatly increases the surface area of the root. B. is a waterproof band surrounding the endodermis. C. directs the movement of water from one cell s cytoplasm to the next through plasmodesmata. D. secretes suberin, which waterproofs the cells. E. allows nutrient minerals to move against their concentration gradient. 19. The center of a primary eudicot root is known as the: A. phloem. B. symplast. C. cortex. D. pericycle. E. stele. 20. Which is the correct horizontal pathway of water from the soil to the center of the root? A. epidermis root hair cortex pericycle endodermis xylem B. epidermis cortex pericycle endodermis phloem xylem C. root hair epidermis cortex endodermis pericycle xylem D. root hair cortex endodermis pericycle epidermis xylem E. root hair epidermis endodermis cortex xylem phloem 36-3
21. Which of the following examples demonstrates a mutualistic relationship? A. mycorrhizae B. rhizobia and root nodules C. soil fungus and soil bacteria D. mistletoe and its host E. Both mycorrhizae and rhizobia/root nodules. 22. What group of organisms fixes nitrogen? A. bacteria B. earthworms C. fungi D. protozoa E. algae 23. Cation exchange between soil particles and root hairs is the process in which: A. protons are exchanged for positively charged mineral ions. B. electrons are exchanged for positively charged mineral ions. C. protons are exchanged for negatively charged mineral ions. D. electrons are exchanged for negatively charged mineral ions. E. water is exchanged for positively charged mineral ions. 24. The partly decayed organic portion of soil is called: A. silt. B. clay. C. sand. D. humus. E. castings. 25. Which of the following statements about acid precipitation is false? A. It can decrease soil ph. B. It is implicated in forest decline. C. It drops sulfuric and nitric acids on the Earth. D. It is caused by human activities. E. None of these; all are true statements about acid precipitation. 26. Which of the following elements is a macronutrient in plants? A. sodium B. calcium C. manganese D. zinc E. copper 27. Which of the following elements is a micronutrient in plants? A. chlorine B. hydrogen C. potassium D. calcium E. magnesium 36-4
28. Which of the following elements is correctly matched with its major function in plants? A. phosphorus alters membrane permeability B. sulfur essential part of chlorophyll C. potassium opens and closes stomata D. carbon maintains turgidity of cells E. calcium involved in nitrogen-fixation 29. What are the three elements that are most often limiting factors for plant growth? A. carbon, potassium, and magnesium B. carbon, oxygen, and nitrogen C. hydrogen, magnesium, and oxygen D. sulfur, calcium, and nitrogen E. nitrogen, phosphorus, and potassium 30. Irrigation can cause salt to accumulate in the soil, a process known as: A. erosion. B. decomposition. C. mineralization. D. salinization. E. weathering. 31. The union of gametes is called and takes place within the of a flower. A. fertilization; ovary B. fission; anther C. meiosis; receptacle D. mitosis; pistil E. fusion; stamen 32. Asexual reproduction in flowering plants does not usually involve the formation of: A. plantlets, stolons, or seeds. B. suckers, corms, or rhizomes. C. flowers, seeds, or fruits. D. bulbs, rhizomes, or seeds. E. flowers, bulbs, or stolons. 33. The diploid portion of a plant life cycle is known as the: A. parental generation. B. sporophyte generation. C. daughter generation. D. gametophyte generation. E. reproductive generation. 34. In angiosperms, the gametophyte generation: A. results from the fertilization of two gametes. B. is dominant. C. is nutritionally dependent on the sporophyte. D. produces gametes via meiosis. E. All of these. 36-5
35. On the accompanying figure, the structure in which the formation of eggs would occur is labeled. A. 1 B. 5 C. 6 D. 9 E. 10 36. The structure in which you would find microsporocytes is labeled in the accompanying figure. A. 1 B. 2 C. 6 D. 9 E. 10 37. The order of whorls from the flower s periphery to the center is: A. sepals, petals, stamens, and carpels. B. carpels, petals, stamens, and sepals. C. petals, carpels, stamens, and sepals. D. sepals, carpels, stamens, and calyx. E. calyx, carpels, stamens, and sepals. 38. Flower parts are borne on the tip of a stalk referred to as the: A. calyx. B. corolla. C. filament. D. receptacle. E. stigma. 39. All the sepals of a flower are collectively known as the: A. calyx. B. carpel. C. corolla. D. pistil. E. receptacle. 36-6
40. Each pollen grain produces two cells, one of which may develop into: A. a polar nucleus. B. a pollen tube. C. an anther. D. a compound pistil. E. a filament. 41. The female plant structure on which a pollen grain will land is the: A. style. B. pistil. C. stigma. D. anther. E. style. 42. Which statement about the megasporocyte is true? A. It undergoes meiosis to produce three haploid cells. B. It is a diploid cell located within an ovule. C. It divides mitotically to form a male gametophyte. D. It plays an important role in cross-pollination. E. It will give rise to the generative cell. 43. What mechanism is used to prevent self-pollination in angiosperms? A. separate male and female individuals B. pollen is shed before the stigma of that flower is receptive to pollen C. pollen is shed after the stigma of that flower is receptive to pollen D. self-incompatibility genes E. All of these. 44. Most flowers are pollinated by which method? A. wind B. birds C. bats D. water E. insects 45. Genes for self-incompatibility usually inhibit the: A. production of pollen grains. B. pollination. C. growth of the pollen tube. D. growth of the style. E. microspore formation. 46. Flowers that are strongly odiferous and blue or UV purple in color would most likely be pollinated by: A. insects. B. birds. C. bats. D. wind. E. small rodents. 36-7
47. Certain orchids produce flowers and secrete scents that resemble female bees so that male bees will mount these flowers and attempt to copulate with them. This bizarre occurrence is an example of: A. fertilization. B. coevolution. C. apomixis. D. self-pollination. E. asexual reproduction. 48. Plants that produce scentless, inconspicuous flowers with enormous amounts of pollen are adapted to which type of pollination? A. wind B. birds C. bats D. small rodents E. insects 49. The fusion of a sperm cell with two polar nuclei in the ovule forms the: A. cotyledon. B. endosperm. C. fertilized egg. D. zygote. E. embryo. 50. Following double fertilization, the ovule develops into, and the ovary develops into. A. a cotyledon; an embryo B. an embryo; a seed C. a seed; a fruit D. a fruit; a seed E. an endosperm; an embryo Use the figure to answer the corresponding questions. 51. On the accompanying figure, the structure containing most of the food used by the embryonic plant during germination is labeled: A. 2. B. 3. C. 4. D. 5. E. None of these. 52. Structures labeled 4 in the figure: A. are the cotyledons. B. indicate that this plant is a dicot. C. are part of the embryo. D. are surrounded by endosperm. E. All of these. 36-8
53. Which is the correct sequence of embryonic development in dicots? A. globular embryo suspensor embryo proembryo heart stage embryo B. heart stage embryo globular embryo proembryo torpedo stage embryo C. torpedo stage embryo globular embryo heart stage embryo suspensor embryo D. proembryo torpedo stage embryo heart stage embryo globular embryo E. proembryo globular embryo heart stage embryo torpedo stage embryo 54. What is the function of cotyledons in many plants? A. to enclose and protect the seed B. to act as a short embryonic root C. to produce pollen D. to store food reserves E. to aid in seed dispersal 55. Which of the following is a structure adapted for seed dispersal by animals? A. light, feathery plumes B. thick, indigestible seed coats C. air spaces and cork D. turgor pressure within fruits E. winged fruits 56. Plants that flower when the length of darkness is equal to or greater than the critical period for that plant are referred to as: A. solar trackers. B. long-day plants. C. nocturnal plants. D. short-day plants. E. day-neutral plants. 57. Plants that do not begin to flower in response to seasonal changes in the period of light and darkness, but instead respond to some other type of stimulus, are called: A. long-day plants. B. short-day plants. C. day-neutral plants. D. vernalized plants. E. intermediate-day plants. 58. The absorption of water by a dry seed is known as: A. apical dominance. B. determinate growth. C. imbibition. D. senescence. E. bolting. 36-9
59. The prolonged low temperature exposure required for the germination of some seeds: A. is typical of coconuts. B. provides an alternative to the process of imbibition. C. prevents them from growing in flooded, anaerobic soils. D. allows the seeds to conserve limited food stores. E. ensures that the seeds germinate in spring, rather than in winter. 60. The term for mechanical injury to the seed coat that induces germination is: A. imbibition. B. scarification. C. bolting. D. vernalization. E. thigmomorphogenesis. 61. The first part of the seedling to come out during germination is: A. plumule. B. radicle. C. cotyledons. D. leaves. E. coleoptile. 62. Corn and other grasses have a unique sheath of cells known as the that surrounds and protects the young shoot. A. coleoptile B. coleorhizum C. cotyledon D. endosperm E. radicle 63. A is an underground stem that is greatly enlarged for food storage. A. sucker B. runner C. plantlet D. stolon E. tuber 64. Which of the following is an example of a modified underground bud with fleshy leaves for storage? A. onion B. white potato C. gladiolus D. ginger E. strawberry 65. Rhizomes, tubers, corms, and stolons are examples of modified: A. leaves. B. flowers. C. roots. D. bulbs. E. stems. 36-10
66. Sometimes plants produce embryos in seeds without meiosis and fusion of gametes. This process is known as: A. coevolution. B. apomixis. C. self-pollination. D. mitosis. E. suckering. 67. Costs associated with sexual reproduction in plants include all of the following except: A. both male and female plants or structures are required. B. death rates are high among offspring. C. gametes must come together in order for fertilization to take place. D. flowers have adapted to attract pollinators. E. offspring have a fitness equal to that of their parents. 68. Changing day length, as well as variations in precipitation and temperature, are environmental cues that exert an important influence on: A. the kinds of genes a plant has. B. the number of mutations that genes undergo. C. whether a plant is an annual, biennial, or perennial. D. which genes will be expressed in a plant. E. whether a plant reproduces sexually or asexually. 69. Plants respond to all of the following environmental cues except: A. gravity. B. touch. C. day length. D. temperature. E. None of these; plants respond to all of these cues. 70. When a plant responds to external stimuli, such as light, gravity, or touch by directional growth, these responses are referred to as: A. turgor movements. B. sleep movements. C. nastic movements. D. circadian rhythms. E. tropisms. 71. When a root is placed on its side, what happens to the amyloplasts in the root cap cells? A. They move to the top. B. They settle on the bottom. C. They are digested by amylase. D. They move into the root apical meristem. E. They move into a root hair. 36-11
72. is growth in response to a mechanical stimulus, such as contact with a solid object. A. Heliotropism B. Phototropism C. Gravitropism D. Thigmotropism E. Geotropic bending 73. If you placed a coleoptile in unidirectional light and then immediately covered the tip, which of the following would happen? A. The coleoptile would bend toward the light. B. The coleoptile would not bend. C. The coleoptile would bend away from the light. D. The coleoptile would die. E. The coleoptile would grow in a spiral pattern. 74. If you removed a coleoptile tip, placed it on an agar block for a period of time, and then placed the agar block to the side of the tip of a decapitated coleoptile, which of the following would happen next? A. The coleoptile would grow in a spiral pattern. B. The coleoptile would die. C. The coleoptile would not bend. D. The coleoptile would bend away from the side having the agar block. E. The coleoptile would bend toward the side having the agar block. 75. The most common and physiologically important auxin is: A. indoleacetic acid. B. indolebutyric acid. C. naphthaleneacetic acid. D. 2,4-D. E. 2,4,5-T. 76. If you expose a plant to a light that shines on the right side of a plant, which of the following best describes why the plant grows toward the light? A. Light destroys auxin, and thus the shaded side grows faster. B. Auxin moves from the shaded side to the lighted side where it stimulates growth. C. Auxin moves from the lighted side to the shaded side where it stimulates growth. D. Light destroys auxin and thus the lighted side grows faster. E. Auxin moves from the shaded side to the lighted side where it inhibits growth. 77. What hormone promotes apical dominance in plants? A. abscisic acid B. auxin C. cytokinin D. ethylene E. gibberellin 36-12
78. What is the hormone that promotes stem elongation and was first discovered while studying the growth of extremely tall and spindly rice plants? A. abscisic acid B. auxin C. cytokinin D. ethylene E. gibberellin 79. What am I? I am present in reduced amounts in dwarf plants, and I stimulate bolting in many species. A. abscisic acid B. gibberellin C. cytokinin D. ethylene E. auxin 80. In barley seed germination, the releases gibberellin which triggers the synthesis of in the. A. seed coat; α-amylase; embryo B. endosperm; cellulase; embryo C. embryo; α-amylase; endosperm D. embryo; cellulase; seed coat E. endosperm; β-amylase; embryo 81. Which hormone promotes cell division and delays senescence in plants? A. abscisic acid B. auxin C. cytokinin D. ethylene E. gibberellin 82. Which hormone stimulates both leaf abscission and fruit ripening? A. abscisic acid B. auxin C. cytokinin D. ethylene E. gibberellin 83. The stress hormone involved in stomatal closure during water stress is: A. abscisic acid. B. auxin. C. cytokinin. D. ethylene. E. gibberellin. 84. What am I? I am structurally related to aspirin, and I help defend plants against insect attack. A. systemin B. jasmonates C. brassinosteroids D. salicylic acid E. oligosaccharins 36-13
85. What hypothetical hormone promotes flowering but has never been successfully isolated? A. florigen B. oligosaccharin C. systemin D. brassinolide E. salicylic acid 86. Any response of a plant to the relative lengths of light and darkness is referred to as: A. gravitropism. B. photoperiodism. C. phototropism. D. thigmotropism. E. thigmomorphogenesis. 87. The photoreceptor for photoperiodism and some other light-initiated plant responses is a group of blue-green pigments named: A. xanthophyll. B. carotene. C. chlorophyll. D. phytochrome. E. phycocyanin. DISCUSSION OR THOUGHT QUESTIONS-type thoughtful answers on a separate sheet of paper. 1. How is it possible for water to defy gravity and travel from the roots to the tops of plants? Use the tension-cohesion model to explain your answer. 2. Explain how dissolved sugar is transported in the phloem by means of a pressure gradient. 3. Differentiate between 2 of the following specialized roots: A. prop root B. buttress root B. pneumatophore C. storage root D. photosynthetic root 4. Why are living organisms such an important component of soil? 5. What is the significance of double fertilization in flowering plants? 36-14