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1) What is an advantage of using organic fertilizer that is not true for inorganic fertilizer?

a. It contains all three major nutrients: N, P, and K.b. It contains carbohydrates that plants use.c. It is made in controlled industrial processes.d. It releases nutrients more slowly, resisting leaching.e. Its nutrients are immediately available to plants.

2) Which of the following is an example of phytoremediation?a. Plants secrete H+ ions that modify the soil pH.b. The mesh of roots holds soil in place, preventing erosion.c. Plants take in atmospheric CO2, limiting global warming.d. Plant decomposition returns many minerals to the soil.e. Plants take up and concentrate excess zinc from soils.

3) All of the following contributed to the dust bowl in the American southwest during the 1930s except A) overgrazing by cattle. B) clear cutting of forest trees. C) plowing of native grasses. D) planting of field crops. E) lack of soil moisture.

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4) For this pair of items, choose the option that best describes their relationship.(A) The number of essential macronutrients required by plants(B) The number of essential micronutrients required by plants

a. Item (A) is greater than item (B). b. Item (A) is less than item (B). c. Item (A) is exactly or very approximately equal to item (B). d. Item (A) may stand in more than one of the above relations to item (B).

5) There are several properties of a soil in which typical plants would grow well. Of the following, which would be the least conducive to plant growth?

A) abundant humus B) numerous soil organisms C) compacted soil D) high porosity E) high cation exchange capacity

6) A soil well suited for the growth of most plants would have all of the following properties except

A) abundant humus. B) air spaces. C) good drainage. D) high cation exchange capacity. E) a high pH.

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The following figure shows the results of a study to determine the effect of soil air spaces on plant growth.

12) The best conclusion from the data in Figure 37.1 is that the plant

A) grows best without air in the soil. B) grows fastest in 5 to 10% air. C) grows best at soil air levels above 15%. D) does not respond differently to different levels of air in the soil. E) would grow to 24 grams in 40% soil air.

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15) Why does over-watering a plant kill it?

A) Water does not have all the necessary minerals a plant needs to grow. B) Water neutralizes the pH of the soil. C) The roots are deprived of oxygen. D) Water supports the growth of root parasites. E) Water lowers the water potential of the roots.

18) The N-P-K percentages on a package of fertilizer refer to the

A) total protein content of the three major ingredients of the fertilizer. B) percentages of manure collected from different types of animals. C) relative percentages of organic and inorganic nutrients in the fertilizer. D) percentages of three important mineral nutrients. E) proportions of three different nitrogen sources.

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In west Texas, cotton has become an important crop in the last several decades. However, in this hot, dry part of the country there is little rainfall, so farmers irrigate their cotton fields. They must also regularly fertilize the cotton fields because the soil is very sandy. The following figure shows the record of annual productivity (measured in kilograms of cotton per hectare of land) since 1960 in a west Texas cotton field. Use these data to answer the following questions.

19) Based on the information provided above, what is the most likely cause of the decline in productivity?

A) The farmer used the wrong kind of fertilizer. B) The cotton is developing a resistance to the fertilizer and to irrigation water. C) Water has accumulated in the soil due to irrigation. D) The soil water potential has become more negative due to salination. E) The rate of photosynthesis has declined due to irrigation.

20) If you were the county agriculture agent, what would be the best advice you could give the farmer who owns the field under study in Figure 37.2?

A) Plant a variety of cotton that requires less water and can tolerate salinity. B) Continue to fertilize, but stop irrigating and rely on rainfall. C) Continue to irrigate, but stop fertilizing and rely on organic nutrients in the soil. D) Continue to fertilize and irrigate, but add the nitrogen-fixing bacteria Rhizobium to the irrigation water until the productivity increases. E) Add acid to the soil and increase its cation exchange capabilities so more nutrients are retained in the soil.

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27) In hydroponic culture, what is the purpose of bubbling air into the solute? A) to keep dissolved nutrients evenly distributed B) to provide oxygen to the root cells C) to inhibit the growth of aerobic algae D) to inhibit the growth of anaerobic bacteria E) to provide CO2 for photosynthesis 31) Which two elements make up more than 90% of the dry weight of plants? A) carbon and nitrogen B) oxygen and hydrogen C) nitrogen and oxygen D) oxygen and carbon E) carbon and potassium 33) What are the three main elements on which plant growth and development depend? A) nitrogen; carbon; oxygen B) potassium; carbon; oxygen C) oxygen; carbon; hydrogen D) phosphorus; nitrogen; oxygen E) sulfur; nitrogen; phosphorus

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34) A growing plant exhibits chlorosis of the leaves of the entire plant. The chlorosis is probably due to a deficiency of which of the following macronutrients? A) carbon B) oxygen C) nitrogen D) calcium E) hydrogen

35) Which of the following elements is incorrectly paired with its function in a plant? A) Nitrogen component of nucleic acids, proteins, hormones, coenzymes B) Magnesium component of chlorophyll; activates many enzymes C) Phosphorus component of nucleic acids, phospholipids, ATP, several coenzymes D) Potassium cofactor functional in protein synthesis; osmosis; operation of stomata E) Sulfur component of DNA; activates some enzymes

36) Which element is important in the formation and stability of cell walls? A) zinc B) chlorine C) calcium D) molybdenum E) Manganese

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41) Reddish-purple coloring of leaves, especially along the margins of young leaves, is a typical symptom of deficiency of which element? A) C B) M++ C) N D) P E) K+

44) What is meant by the term chlorosis? A) the uptake of the micronutrient chlorine by a plant B) the formation of chlorophyll within the thylakoid membranes of a plant C) the yellowing of leaves due to decreased chlorophyll production D) a contamination of glassware in hydroponic culture E) release of negatively charged minerals such as chloride from clay particles in soil

47) Nitrogen fixation is a process that A) recycles nitrogen compounds from dead and decaying materials. B) converts ammonia to nitrate. C) releases nitrate from the rock substrate. D) converts nitrogen gas into ammonia. E) A and B

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49) In what way do nitrogen compounds differ from other minerals needed by plants? A) Only nitrogen can be lost from the soil. B) Only nitrogen requires the action of bacteria to be made available to plants. C) Only nitrogen is needed for protein synthesis. D) Only nitrogen is held by cation exchange capacity in the soil. E) Only nitrogen can be absorbed by root hairs.

50) Most crop plants acquire their nitrogen mainly in the form of A) NH3. B) N2. C) CN2H2. D) NO3.. E) amino acids absorbed from the soil.

51) The enzyme complex nitrogenase catalyzes the reaction that reduces atmospheric nitrogen to A) N2. B) NH3. C) NO2. D) NO+. E) NO-.

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55) If a plant is infected with Rhizobium, what is the probable effect on the plant? A) It gets chlorosis. B) It dies. C) It is supplied with phosphate from the soil. D) It probably will grow faster E) It becomes flaccid due to the loss of water from the roots

58) What is the function of a root nodule's leghemoglobin? A) extract macronutrients from the soil. B) regulate the supply of oxygen to Rhizobium. C) promote ion exchange in the soil. D) form a mutualistic relationship with insects. E) supply the legume with fixed nitrogen. TRUE OR FALSE

68) Phytoremediation is a biotechnology that uses the ability of some plants to extract soil pollutants and concentrate them in portions of the plant that can be easily removed for safe disposal.

69) Plant roots excrete substances that bind the soil particles and raise the soil pH. 70) Macronutrients, elements required in relatively large amounts, typically have catalytic functions as cofactors of enzymes.

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10) Carnivorous adaptations of plants mainly compensate for soil that has a relatively low content of A) potassium. B) nitrogen. C) calcium. D) water. E) phosphate. ________________________________________________________________________

Draw a simple sketch of cation exchange, showing a root hair, a soil particle with anions, and a hydrogen ion displacing the potassium (K+) mineral cation.

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A horizon contains _________________________________

B horizon contains _________________________________

C horizon contains _________________________________

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Define the following terms:

Humus:

Loam:

Subsidence:

Salinization:

No-till Agriculture:

Mutualistic Relationship:

Rizosphere:

14

Name the Deficiency:

Healthy

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•Ammonium is made available to plants by 2 types of soil bacteria.

1)

2)

AtmosphereAtmosphere

Soil

Nitrogen-fixing bacteria

Soil

H+

(from soil)

Ammonifyingbacteria

NH4+

(ammonium) Nitrifyingbacteria

Organic material (humus)

N2

NO3–

(nitrate)

Denitrifyingbacteria

NH4+

Nitrate andnitrogenous

organiccompoundsexported in

xylem toshoot system

Root

Fill in the missing words.

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Fill in the blanks.

Nitrification is carried out by ________that convert _______(___) into _______ions (____).

Inside the root nodule, ____________ bacteria assume a form called ___________, which are contained within vesicles formed by the root cell.

__________rotation takes advantage of the agricultural benefits of symbiotic nitrogen fixation.

Instead of being harvested, the legume crop is often plowed under to decompose as “green manure” and reduce the need for manufactured_____________.

_________________ are mutualistic associations of fungi and roots.

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RhizobiumbacteriaInfection thread

Chemical signalsattract bacteria

1

1

2

2

3

34

4

Infected root hair

BacteroidBacteroids form

Dividing cellsin root cortex

Dividing cells inpericycle

Developingroot nodule

Bacteroid

Noduleforms

NodulevasculartissueBacteroid

Nodule developsvascular tissue

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Epidermis Cortex Mantle(fungalsheath)

Endodermis

Fungalhyphaebetweencorticalcells (colorized SEM)

100 µm

Mantle(fungal sheath)

(a) Ectomycorrhizae

Define the following:Ectomycorrhizae:

Arbuscular mycorrhizae:

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Epidermis

Fungalhyphae

Cortex

Endodermis

Fungalvesicle

Casparianstrip

Arbuscules

Plasmamembrane

Roothair

(b) Arbuscular mycorrhizae (endomycorrhizae)

Cortical cells 10 µm

(LM, stained specimen)

What is the difference between ectomycorrhizae and arbuscular mycorrhizae.

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Some plants have nutritional adaptations that use other organisms in nonmutualistic ways. Name the 3 classes and describe the adaptations for each.

1)________________________Adaptation:

2) ________________________Adaptation:

3) ________________________Adaptation:

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1) All of the following may function in signal transduction in plants except A) calcium ions. B) nonrandom mutations. C) receptor proteins. D) phytochrome. E) second messengers. 2) External stimuli would be received most quickly by a plant cell if the receptors for signal transduction were located in the A) cell membrane. B) cytoplasmic matrix. C) endoplasmic reticulum. D) nuclear membrane. E) nucleoplasm. 3) Charles and Francis Darwin concluded from their experiments on phototropism by grass seedlings that the part of the seedling that detects the direction of light is the A) tip of the coleoptile. B) part of the coleoptile that bends during the response. C) base of the coleoptile. D) cotyledon. E) phytochrome in the leaves.

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8) We know from the experiments of the past that plants bend toward light because A) they need sunlight energy for photosynthesis. B) the sun stimulates stem growth. C) cell expansion is greater on the dark side of the stem. D) auxin is inactive on the dark side of the stem. E) phytochrome stimulates florigen production.

11) According to modern ideas about phototropism in plants, A) light causes auxin to accumulate on the shaded side of a plant stem. B) auxin stimulates elongation of plant stem cells. C) auxin is produced by the tip of the coleoptile and moves downward. D) A and B only E) A, B and C

12) A plant seedling bends toward sunlight because A) auxin migrates to the lower part of the stem due to gravity. B) there is more auxin on the light side of the stem. C) auxin is destroyed more quickly on the dark side of the stem. D) auxin is found in greatest abundance on the dark side of the stem. E) gibberellins produced at the stem tip cause phototropism.

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19) The plant hormone involved in aging and ripening of fruit is A) auxin. B) ethylene. C) florigen. D) abscisic acid. E) gibberellin. 23) Plant hormones produce their effects by A) altering the expression of genes. B) modifying the permeability of the plasma membrane. C) modifying the structure of the nuclear envelope membrane. D) both A and B E) B and C only 25) Buds and sprouts often form on tree stumps. Which of the following hormones would you expect to stimulate their formation? A) auxin B) cytokinins C) abscisic acid D) ethylene E) Gibberellins

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31) Which plant hormones might be used to enhance stem elongation and fruit growth? A) brassinosteroids and oligosaccharides B) auxins and gibberellins C) abscisic acid and phytochrome D) ethylene and cytokinins E) phytochrome and flowering hormone 35) Which of the following hormones would be most useful in promoting the rooting of plant cuttings? A) oligosaccharins B) abscisic acid C) cytokinins D) gibberellins E) auxins

36) Which plant hormone(s) is (are) most closely associated with cell division? A) ethylene B) cytokinin C) abscisic acid D) phytochrome E) Brassinosteroids

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37) The heavy line in this figure illustrates the relationship between auxin concentration and cell growth in stem tissues. If the same range of concentrations were applied to lateral buds, what curve would probably be produced? A) I B) II C) III D) II and III E) either I or III

38) The synthesis of which of the following hormones would be a logical first choice in an attempt to produce normal growth in mutant dwarf plants? A) indoleacetic acid B) cytokinin C) gibberellin D) abscisic acid E) Ethylene

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39) The results of this experiment, shown on the left of the graph (area A), may be used to A) show that these plants can live without gibberellin. B) show that gibberellin is necessary in positive gravitropism. C) show that taller plants with more gibberellin produce fruit (pods). D) show a correlation between plant height and gibberellin concentration. E) study phytoalexins in plants.

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55) Most plants close their stomata at night. What color of light would be most effective in promoting stomatal opening in the middle of the night? A) red B) far-red C) blue D) red followed by far-red E) far-red followed by blue

59) The biological clock controlling circadian rhythms must ultimately A) depend on environmental cues. B) affect gene transcription. C) stabilize on a 24-hour cycle. D) speed up or slow down with increasing or decreasing temperature. E) do all of the above.

61) If the range of a species of plants expands to a higher latitude, which of the following processes is the most likely to be modified by natural selection? A) circadian rhythm B) photoperiodic response C) phototropic response D) biological clock E) thigmomorphogenesis

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75) If you wanted to genetically engineer a plant to be more resistant to drought, increasing amounts of which of the following hormones might be a good first attempt? A) abscisic acid B) brassinosteroids C) gibberellins D) cytokinins E) auxin

78) In extremely cold regions, woody species may survive freezing temperatures by A) emptying water from the vacuoles to prevent freezing. B) decreasing the numbers of phospholipids in cell membranes. C) decreasing the fluidity of all cellular membranes. D) producing canavanine as a natural antifreeze. E) increasing cytoplasmic levels of specific solute concentrations, such as sugars. 82) In general, which of the following is not a plant response to herbivores? A) domestication, so that humans can protect the plant B) attracting predatory animals, such as parasitoid wasps C) chemical defenses, such as toxic compounds D) physical defenses, such as thorns E) production of volatile molecules

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83) In order for a plant to initiate chemical responses to herbivory, A) the plant must be directly attacked by an herbivore. B) volatile "signal" compounds must be perceived. C) gene-for-gene recognition must occur. D) phytoalexins must be released. E) all of the above must happen. 87) The transduction pathway that activates systemic acquired resistance in plants is initially signaled by A) antisense RNA. B) Pfr phytochrome. C) salicylic acid. D) abscisic acid. E) red, but not far-red, light.

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TRUE OR FALSE

96) A long-day plant will flower only when the night is longer than a critical value.

97) Roots exhibit negative gravitropism whereas stems exhibit positive gravitropism. 98) The rapid leaf movements resulting from a response to touch (thigmotropism) involve transmission of electrical impulses called action potentials. 99) Plant hormonal control differs from animal hormonal control in that there are no separate hormone producing organs in plants as there are in animals. 100) Unlike animal hormones, plant hormones are primarily involved in regulating growth and development.

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CELLWALL

CYTOPLASM

Transduction

Relay proteins and

second messengers

Activationof cellularresponses

Hormone orenvironmental stimulus

Receptor

Plasma membrane

1 2 3

Fill in the blanks.

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CYTOPLASM

Reception

Plasmamembrane

Cellwall

Phytochromeactivated by light

Light

Transduction

Second messenger produced

cGMP Specific protein

kinase 1 activated

NUCLEUS

1 2

Specific protein kinase 2 activated

Ca2+ channel opened

Ca2+

Response3

Transcriptionfactor 1

Transcriptionfactor 2

NUCLEUS

Transcription

Translation

De-etiolation(greening)responseproteins

P

P

Fill in the blanks.

33

34

Ethylene concentration (parts per million)

0.100.00 0.20 0.40 0.80

Describe what is going on in this experiment.

35

Dark (control)

DarkRed

Red Far-red Red Dark Red Far-red Red Far-red

Red Far-red Dark

Describe what is going on in this experiment.

36

Synthesis

Pr

Far-redlight

Slow conversionin darkness(some plants)

Enzymaticdestruction

Responses:seed germination,control offlowering, etc.

Pfr

Red light

37

Describe what is going on in this experiment.

38

Define:Photoperiod:

Florigen:

Gravitropism:

Statoliths:

Thigmotropism:

Heat-shock Proteins:

Methyljasmonic acid:

Virulent:

R-genes:

Gene-for-gene recognition :

Systemic acquired resistance :

AND…..KNOW

Figure 39.29 Defense Responses against avirulent pathogens.