Plant Science
Exam Answer Key
Course Introduction
Plant Science is an interdisciplinary course that explores the biology, physiology, and ecology of plants, emphasizing their fundamental roles in ecosystems and human societies. Students will examine plant structure, growth, and reproduction, as well as processes such as photosynthesis, respiration, and nutrient uptake. The course also covers topics like plant genetics, diversity, adaptation, and the impact of environmental factors on plant development. Through lectures, laboratory exercises, and fieldwork, students gain practical skills in plant identification, propagation, and experimental design, preparing them for advanced studies or careers in agriculture, horticulture, environmental science, and related fields.
Recommended Textbook
The Nature and Properties of Soils 14th Edition by Nyle C. Brady
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20 Chapters
838 Verified Questions
838 Flashcards
Source URL: https://quizplus.com/study-set/3989 Page 2
Chapter 1: The Soils Around US
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42 Verified Questions
42 Flashcards
Source URL: https://quizplus.com/quiz/80115
Sample Questions
Q1) Information about conditions at 2 to 4 meters deep in a soil is usually most helpful for understanding___.
A)how best to design a building foundation
B)the diversity of animal life in the soil.
C)the proper classification of the soil.
D)fertility requirements of most crops
Answer: A
Q2) Increasing the organic matter content of a soil is likely to _____.
A)have no effect on water holding capacity
B)increase the soil's water holding capacity
C)decrease the soil's water holding capacity
Answer: B
Q3) The dark brown and black humus found in many soils does not mix well with clay minerals so there is very little contact between these two soil components.
A)True
B)False
Answer: False
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Chapter 2: Formation of Soils From Parent Materials
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53 Verified Questions
53 Flashcards
Source URL: https://quizplus.com/quiz/80116
Sample Questions
Q1) The C horizons are generally more completely weathered than the other horizons.
A)True
B)False
Answer: False
Q2) The presence of iron in a mineral generally increases its resistance to chemical breakdown.
A)True
B)False
Answer: False
Q3) Even if all the glaciers present today in the world were to melt, the melt water would have no measurable effect on the level of the world's oceans.
A)True
B)False
Answer: False
Q4) Climate influences not only the rate of weathering but the type of native vegetation dominant in an area.
A)True
B)False Answer: True
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Chapter 3: Soil Classification
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47 Verified Questions
47 Flashcards
Source URL: https://quizplus.com/quiz/80117
Sample Questions
Q1) The categories of Soil Taxonomy can be listed from the broadest (first) and most specific (last) as: order, suborder, great group, subgroup, series, family.
A)True
B)False
Answer: False
Q2) Spodosols are generally less acidic and less sandy than are Alfisols.
A)True
B)False
Answer: False
Q3) Vertisols are characterized by high contents of swelling-type silicate clays.
A)True
B)False
Answer: True
Q4) An argillic horizon is a diagnostic horizon characterized by the subsurface accumulation of silicate clays.
A)True
B)False
Answer: True
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Chapter 4: Soil Architecture and Physical Properties
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43 Verified Questions
43 Flashcards
Source URL: https://quizplus.com/quiz/80118
Sample Questions
Q1) The drainage class of a soil (the degree to which the soil becomes water-saturated during the year) can be judged by the presence and location of gley in the soil profile.
A)True
B)False
Q2) Polysaccharides produced by soil microbes and similar synthetic polymers applied to soils are largely responsible for the crusts that form when rain follows tillage.
A)True
B)False
Q3) Fungal hyphae have an important influence on soil structure because they ______.
A)help to flocculate the soil colloids
B)stabilize macro aggregates
C)are active in the formation of soils crusts
D)create large channels that enhance water flow and aeration
E)all of the above
Q4) Subsoiling is a primitive deep tillage technique that results in extremely high subsoil bulk density.
A)True
B)False
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Chapter 5: Soil Water: Characteristics and Behavior
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39 Verified Questions
39 Flashcards
Source URL: https://quizplus.com/quiz/80119
Sample Questions
Q1) The property of cohesion in water stems from the attraction of water molecules for soil solids.
A)True
B)False
Q2) The effect of soil organic matter on the amount of water available to plants is due to organic matter influence on total soil porosity as well as to the water-supplying power of the soil organic matter.
A)True
B)False
Q3) Capillarity in soils _____.
A)involves both adhesion and cohesion
B)is enhanced by the symmetrical nature of the water molecule
C)is independent of the matric potential in soils
D)is not involved in the process of water uptake from soils
E)does not account for unsaturated water movement in soils
Q4) Capillary movement is made possible by the processes of cohesion and adhesion. A)True
B)False
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7
Chapter 6: Soil and the Hydrologic Cycle
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44 Verified Questions
44 Flashcards
Source URL: https://quizplus.com/quiz/80120
Sample Questions
Q1) Conservation tillage can have a significant direct effect on transpiration of water from a rapidly growing crop of corn.
A)True
B)False
Q2) Land drainage is beneficial because _____.
A)it increases the alternate of expansion and contraction due to freezing and thawing of soils
B)it increases the water-to-air ratio in the soil pores
C)it slows down the rate of soil warming in the spring
D)it increases the depth of root penetration in the soil
E)it increases the availability of iron and manganese in acid soils
Q3) Of the various types of drain systems, open ditch systems are most practical and economical for use on __________.
A)Vertisols
B)soils which do not freeze during the winter
C)soils with a deep water Table
D)poorly drained soils with sandy profiles
E)clay soils with poor drainage
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Chapter 7: Soil Aeration and Temperature
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41 Verified Questions
41 Flashcards
Source URL: https://quizplus.com/quiz/80121
Sample Questions
Q1) The most important management factors influencing soil aeration in well-drained soils are those that determine the volume of the soil's macropores.
A)True
B)False
Q2) The great bulk of gaseous interchange between the soil pores and the atmosphere occurs by mass flow of the concerned gases.
A)True
B)False
Q3) The process of aerobic respiration is a significant source of which of the following gases?
A)methane
B)oxygen
C)nitrogen
D)carbon dioxide
E)ammonia
Q4) If the CO<sub>2</sub> content of soil air is 3.5%, it is 100 times higher than that of the atmosphere.
A)True
B)False
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Chapter 8: Soil Colloids: Seat of Soil Chemical and Physical
Activity
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40 Verified Questions
40 Flashcards
Source URL: https://quizplus.com/quiz/80122
Sample Questions
Q1) Anion exchange by formation of outer sphere complexes is of least importance in the plant absorption of _____.
A)NO<sub>3</sub><sup>-</sup>
B)Cl<sup>-</sup>
C)SO<sub>4</sub><sup>2-</sup>
D)MoO<sub>4</sub><sup>-2</sup>
E)H<sub>2</sub>PO<sub>4</sub><sup>-</sup>.
Q2) Even at pH values near 7.0 some colloids such as iron and aluminum oxides have negative surface charges less than 10 cmol<sub>c</sub>/kg.
A)True
B)False
Q3) A well drained soil under a rain forest in Brazil contains significant amounts of a silicate clay.Which of the following is it most apt to be?
A)chlorite
B)fine-grained mica
C)smectite
D)kaolinite
E)vermiculite
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Chapter 9: Soil Acidity
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42 Verified Questions
42 Flashcards
Source URL: https://quizplus.com/quiz/80123
Sample Questions
Q1) Poor plant growth in a well-drained irrigated soil in an arid region (pH=8.0) is most likely due to ________.
A)manganese toxicity
B)iron deficiency
C)phosphate toxicity
D)calcium toxicity
E)molybdenum deficiency
Q2) If you want to grow azaleas in a soil that initially has a pH of 6.5 and have been told that you should apply sulfur to reduce the soil pH, you would likely need more sulfur if the soil is a clay Vertisol than if it is an clay Ultisol.
A)True
B)False
Q3) The buildup of excess salts in irrigated soils can result in increased pH if the salts are high in sodium bicarbonate.
A)True
B)False
Q4) The amount of exchangeable acidity is much smaller than the residual acidity.
A)True
B)False
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Chapter
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41 Verified Questions
41 Flashcards
Source URL: https://quizplus.com/quiz/80124
Sample Questions
Q1) Saline-sodic soils have electrical conductivities greater than 4 dS/m and a sodium adsorption ratio of less than 13.
A)True
B)False
Q2) The degradation of irrigated soils across the once very productive "Fertile Crescent" of the Middle East was due primarily to _____.
A)high calcium and magnesium levels in the irrigation waters
B)high levels of calcium-containing salt in the irrigation water
C)inadequate equipment and power to properly cultivate the soil
D)poor internal drainage of the soils
E)destructive wars in the region
Q3) Irrigation waters with high sodium adsorption (SAR) ratios are preferred over those with lower ratios.
A)True
B)False
Q4) The high pH of sodic soils is due to the high saturation of the colloidal complex with calcium.
A)True
B)False
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Chapter 11: Organisms and Ecology of the Soil
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41 Verified Questions
41 Flashcards
Source URL: https://quizplus.com/quiz/80125
Sample Questions
Q1) Organisms which use carbon dioxide or carbonates for their carbon source and either sunlight or inorganic chemicals for their energy source are called ____.
A)facultative anaerobes
B)heterotrophs
C)detritivores
D)autotrophs
E)actinomycetes
Q2) In most soils the overall population (numbers) of microorganisms changes with time, generally following changes in the _____.
A)supply of decomposable organic matter
B)supply of oxygen
C)porespace
D)availability of root infection sites
E)concentrations of antibiotics
Q3) Termites tend to enrich soils in the tropics much the same way as earthworms do in temperate region soils.
A)True
B)False
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13
Chapter 12: Soil Organic Matter
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41 Verified Questions
41 Flashcards
Source URL: https://quizplus.com/quiz/80126
Sample Questions
Q1) Which of the following is (are) major sources of the carbon dioxide now being added to the atmosphere in excess of the amount taken out by plants?
A)loss of soil organic matter
B)burning of fossil fuels
C)destruction of natural forests
D)all of the above
E)none of the above
Q2) Allelopathic chemicals, once added to soil, usually make the affected soil unsuitable for any plant life for periods of years.
A)True
B)False
Q3) After drying to eliminate the water in plant litter, which two elements account for about 80% of the dry weight?
A)N and C
B)N and S
C)C and H
D)C and O
E)Ca and C
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14
Chapter 13: Nitrogen and Sulfur Economy of Soils
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41 Verified Questions
41 Flashcards
Source URL: https://quizplus.com/quiz/80127
Sample Questions
Q1) Wetlands and forests growing along the banks of rivers remove much nitrogen from groundwater by the process of _________.
A)immobilization
B)nitrification
C)denitrification
D)ammonification
E)none of the above
Q2) In most temperate, humid regions, the period of greatest potential for nitrate leaching is during the summer when nitrogen fertilizer is applied to crops.
A)True
B)False
Q3) Ammonia volatilization is a process by which much needed nitrogen is added to the pool of plant-available nitrogen in soils.
A)True
B)False
Q4) A deficiency of N typically ______ the maturity of annual plants.
A)hastens
B)delays
C)does not affect
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Chapter 14: Soil Phosphorus and Potassium
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39 Verified Questions
39 Flashcards
Source URL: https://quizplus.com/quiz/80128
Sample Questions
Q1) The nutrient most often limiting the growth of aquatic plants and algae in unpolluted fresh water lakes is ______.
A)N
B)S
C)P
D)K
E)none of the above
Q2) In acid soils the principal chemical form of potassium available for plant uptake is ____.
A)K<sub>2</sub>O
B)H<sub>2</sub>KO<sub>2</sub><sup>-</sup>
C)K<sup>+</sup>
D)HKO<sub>2</sub><sup>2-</sup>
E)P<sup>-</sup>
Q3) Deep rooted vegetation such as forest trees can increase the available potassium content of surface soil horizons even though no potassium is added to the soil profile.
A)True
B)False
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16
Chapter 15: Micronutrients and Other Trace Elements
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42 Verified Questions
42 Flashcards
Source URL: https://quizplus.com/quiz/80129
Sample Questions
Q1) Plant symptoms such as interveinal chlorosis on new leaves suggest a deficiency of which micronutrient?
A)Zn
B)Fe
C)Mn
D)all of the above
E)none of the above
Q2) Which of the following nutrient elements is usually present in the soil solution as a simple cation?
A)B
B)Zn
C)Cl
D)Mo
E)all of the above
Q3) Azaleas, pin oaks and other acid-soil loving forest plants have evolved very efficient mechanisms for extracting iron from soils.
A)True
B)False
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Chapter 16: Practical Nutrient Management
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40 Verified Questions
40 Flashcards
Source URL: https://quizplus.com/quiz/80130
Sample Questions
Q1) Soil test interpretations have been developed so that for most fields testing "low" in a nutrient, addition of that nutrient will increase yield enough to more than pay for the cost of applying the fertilizer.
A)True
B)False
Q2) The nutrient element magnesium is often supplied by which type of application?
A)injection of a gas into the soil
B)broadcast of a chloride salt
C)broadcast of the nearly pure element as a solid
D)incorporation of powdered limestone rock
E)application of a chelate to the soil
Q3) Within the technical capabilities of the particular lab, most soil test results can be best interpreted as indicating the _______________________.
A)total amount of each nutrient in the soil
B)amount (lbs or kg ) of nutrient present in plant available forms
C)amount or concentration of nutrient in the soil solution
D)probability (likelihood) that nutrient application will improve plant growth
E)amount of nutrient needed to achieve balanced soil fertility
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Chapter 17: Soil Erosion and Its Control
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41 Verified Questions
41 Flashcards
Source URL: https://quizplus.com/quiz/80131
Sample Questions
Q1) The surface soil pH is generally higher on no-tillage plots than on comparable conventionally tilled plots.
A)True
B)False
Q2) Slope length is generally of greater significance in determining erosion rate than is steepness of slope.
A)True B)False
Q3) To be classified as a conservation tillage practice, a system must leave at least what portion of the soil surface covered with plant residues?
A)10%
B)20%
C)30%
D)40%
E)50%
Q4) Soils in Land Capability Class VIII areas are less subject to erosion than any other class.
A)True B)False
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Chapter 18: Soils and Chemical Pollution
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41 Verified Questions
41 Flashcards
Source URL: https://quizplus.com/quiz/80132
Sample Questions
Q1) Radionuclides from nuclear power plant accidents and weapons testing pollution get into the food chain primarily by _____.
A)leaching to groundwater supplies
B)uptake from soils into food plants
C)by atmospheric deposition on plant leaves
D)cation exchange
Q2) A pesticide is more likely to contaminate groundwater if it has which of the following characteristics?
A)highly volatile (high vapor pressure)
B)highly soluble in water
C)strongly adsorbed to soil colloids
D)rapidly degraded by soil microorganisms
E)all of the above
Q3) Bioremediation of soils is often brought about by amending the polluted soils with fertilizers containing mineral nutrients.
A)True
B)False
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Chapter 19: Geographic Soils Information
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39 Verified Questions
39 Flashcards
Source URL: https://quizplus.com/quiz/80133
Sample Questions
Q1) The various soils in a catena of soils differ from one another primarily as a result of their geologic parent material.
A)True
B)False
Q2) A lithosequence is _______.
A)a group of soils found together in a landscape that differ principally because of differences in the geologic material in which they formed B)a sequence of steps required to make a lithographic map using information from field observations and air photos
C)a set of soils ranging from well drained to poorly drained D)the proper order of sampling in a transect for determining soil boundaries in the field
Q3) To be effective a geo positioning system receiver must be in contact with at least two different satellites at the same time.
A)True
B)False
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21
Chapter 20: Prospects for Global Soil Quality
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41 Verified Questions
41 Flashcards
Source URL: https://quizplus.com/quiz/80134
Sample Questions
Q1) Which if the following is true about a soil quality index (SQI)?
A)The SQI must be related to a particular functional goal for the soil in the ecosystem.
B)Soil pH, bulk denisty (Mg m<sup>-3</sup>) and soil active C levels (mg kg<sup>-1</sup>) may all be averaged together in a SQI.
C)Soil quality indices may be used to monitor the effects of changes in soil management practice over time.
D)All of the above are true.
E)None of the above are true.
Q2) During the 1990s, the rate of increase of food production has declined.
A)True
B)False
Q3) Worldwide, excesses and/or deficiencies of water reduce crop yields more than any other factor.
A)True
B)False
Q4) There are more hungry people on Earth today than at any time in history
A)True
B)False
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Page 22