Campbell Biology, 10e (Reece)
Chapter 37 Soil and Plant Nutrition
1) What soil composition would be best for availability of nutrients, water, and root
development?
A) equal amounts of sand, clay, and humus
B) higher proportion of humus, lower amounts of clay and sand
C) higher proportion of clay, lower amounts of humus and sand
D) higher proportion of sand, lower amount of humus and clay
2) The highest amount of oxygen will be found in soils containing large amounts of _____.
A) clay
B) sand
C) gravel
D) silt
3) A group of ten tomato plants are germinated and maintained in a large tray with no drainage.
After several weeks they all begin to wilt and die despite repeated watering and fertilization. The
most likely cause of this die-off is _____.
A) competition for resources
B) a lack of oxygen for the roots
C) organic nutrient depletion
D) no room left for root growth
4) There are several properties that are characteristic 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 cation exchange capacity
5) Clay in soils represents a trade-off in nutrient availability, such that _____.
A) anions are less likely to leach out of soil and are difficult for plants to extract
B) cations are less likely to leach out of soil and are difficult for plants to extract
C) nitrogen levels are exceptionally high, but much of the nitrogen leaches away
D) oxygen levels are exceptionally high, but much of the nitrogen leaches away
6) Which of the following soil minerals is most likely leached away during a hard rain?
A) Na+
B) K+
C) Ca++
D) NO3–
7) Which of the following are problems associated with intensive irrigation?
I) mineral runoff
II) over fertilization
III) aquifer depletion
IV) soil salinization
A) only I and II
B) only I, III, and IV
C) only III and IV
D) I, II, III, and IV
8) A young farmer purchases some land in a relatively arid area and is interested in earning a
reasonable profit for many years. Which of the following strategies would best allow the farmer
to achieve such a goal?
A) establishing an extensive irrigation system
B) using plenty of the best fertilizers
C) finding a way to sell all parts of crop plants
D) selecting crops adapted to arid areas
9) The NPK percentages on a package of fertilizer refer to the _____.
A) percentages of manure collected from different types of animals
B) relative percentages of organic and inorganic nutrients in the fertilizer
C) percentages of three important mineral nutrients
D) proportions of three different nitrogen sources
10) Which of the following would inhibit the growth of most plants?
A) abundant humus
B) air spaces
C) good drainage
D) a pH above 10.0
11) Which of the following contributed to the dust bowl in the American southwest during the
1930s?
I) overgrazing by cattle
II) clear-cutting of forest trees
III) plowing of native grasses
IV) lack of soil moisture
A) I and II
B) II, III, and IV
C) I, III, and IV
D) I, II, III, IV
12) Why does planting a cover crop help conserve soil?
I) controls weed populations
II) reduces soil loss due to wind and water erosion
III) increases soil nutrients when plowed under and allowed to decompose
A) only I
B) I and II
C) II and III
D) I, II, and III
13) Which of the following would be the most effective strategy to remove toxic heavy metals
from a soil?
A) heavy irrigation to leach out the heavy metals
B) application of sulfur to lower the soil pH and precipitate the heavy metals
C) adding plant species that have the ability to take up and accumulate heavy metals
D) inoculating soil with mycorrhizae to avoid heavy-metal uptake
14) When comparing root systems of corn plants growing on a square foot in a cornfield with the
root systems of natural prairie plants growing in a meadow, what result do you expect to see?
A) The overall mass of roots will be identical in a cornfield and on a meadow.
B) The mass and length of roots in a cornfield will be higher because soil is fertilized.
C) The mass and length of roots on a meadow will be higher because soil is poorer and there is
higher diversity of plants.
D) The overall mass of roots on a meadow will be lower, but the length will be higher since roots
need to grow deeper to reach nutrients.
15) Most of the dry mass of a plant is the result of uptake of _____.
A) water and minerals through root hairs
B) water and minerals through mycorrhizae
C) carbon dioxide through stoma
D) carbon dioxide and oxygen through stomata in leaves
16) How would you expect the root system of a plant grown by hydroponics to compare to the
root system of a plant grown in soil? The root system of a plant grown by hydroponics would be
_____.
A) more developed
B) less developed
C) about the same
D) absent
17) Which of the following statements about essential nutrients are true? Essential nutrients
_____.
I) are necessary for plant growth and reproduction
II) are required for a specific structure or metabolic function
III) cannot be synthesized by a plant
IV) are produced by symbiotic bacteria
A) I and IV
B) II, III, and IV
C) I, II, and III
D) I, II, III, and IV
18) Which of the following experiments is the best way to determine if an element is essential
for plant growth?
A) Measure the amount of the element stored in plant tissues.
B) Measure the amount of the element in the soil after plant growth.
C) Measure the weight of the plant and soil before and after plant growth.
D) Grow a plant using hydroponics with and without the element.
19) Which criteria allow biologists to divide chemicals into macronutrients and micronutrients?
A) molecular weight of the element or compound
B) the quantities of each required by plants
C) how they are used in metabolism
D) whether or not they are essential for plant growth
20) Which elements are most often the limiting nutrients for plant growth?
A) nitrogen, potassium, phosphorus
B) nitrogen, oxygen, hydrogen
C) carbon, sodium, chlorine
D) carbon, nitrogen, oxygen
21) Synthesis of which of the following compounds in a mature leaf would be least impacted by
a temporary soil nitrogen deficiency?
A) DNA
B) RNA
C) amino acids
D) cellulose
22) A major function of magnesium in plants is to be _____.
A) required to regenerate phosphoenolpyruvate in C4 and CAM plants
B) a component of DNA and RNA
C) a component of chlorophyll
D) active in amino acid formation
23) Micronutrients are needed in very small amounts because _____.
A) most of them are mobile in the plant
B) most serve mainly as cofactors of enzymes
C) they play only a minor role in the growth and health of the plant
D) only the most actively growing regions of the plants require micronutrients
24) Two groups of tomatoes were grown under laboratory conditions, one with humus added to
the soil and one a control without humus. The leaves of the plants grown without humus were
yellowish (less green) compared with those of the plants grown in the humus-enriched soil. The
best explanation for this difference is that _____.
A) the healthy plants used the food in the decomposing leaves of the humus for energy to make
chlorophyll
B) the humus made the soil more loosely packed, so water penetrated more easily to the roots
C) the humus contained minerals such as magnesium and iron, needed for the synthesis of
chlorophyll
D) the heat released by the decomposing leaves of the humus caused more rapid growth and
chlorophyll synthesis
25) Soil leaching can cause nutrient deficiencies in the soil. Which of the following are
symptoms of nutrient deficiency in plants?
I) chlorosis
II) death of meristems
III) excess storage of chlorophyll
IV) small internodes
A) I, II, and III
B) II, III, and IV
C) I, II, and IV
D) I, II, III, and IV
26) If an African violet has chlorosis, which of the following elements might be a useful addition
to the soil?
A) molybdenum
B) copper
C) iodine
D) magnesium
27) Which of the following are characteristic of both rhizobia and mycorrhizae?
I) They both benefit by receiving sugars from the plant.
II) They both become parasitic in nutrient-rich environments.
III) They both enhance the growth of most plants.
IV) They both are found in most ecosystems of the world.
A) only I and II
B) only I, III, and IV
C) only III and IV
D) I, II, III, and IV
28) Which of the following are functions of rhizobacteria?
I) produce hormones that stimulate plant growth
II) produce antibiotics that protect roots from disease
III) absorb toxic metals
IV) carry out nitrogen fixation
A) only II and IV
B) only I, II, and III
C) only III and IV
D) I, II, III, and IV
29) Nitrogen fixation is a process that _____.
A) recycles nitrogen compounds from dead and decaying materials
B) converts ammonia to ammonium
C) releases nitrate from the rock substrate
D) converts nitrogen gas into ammonia
30) Why is nitrogen fixation an essential process?
A) Nitrogen fixation can only be done by certain prokaryotes.
B) Fixed nitrogen is often the limiting factor in plant growth.
C) Nitrogen fixation is very expensive in terms of metabolic energy.
D) Nitrogen fixers are sometimes symbiotic with legumes.
31) You are weeding your garden when you accidentally expose some roots of your pea plants.
You notice swellings (root nodules) on the roots and there is a reddish tinge to the ones you
accidentally damaged. Most likely your peas plants _____.
A) suffer from a mineral deficiency
B) are infected with a parasite
C) are benefiting from a mutualistic bacterium
D) are developing offshoots from the root
32) The specific relationship between a legume and its mutualistic Rhizobium strain probably
depends on _____.
A) each legume having a chemical dialogue with a fungus
B) each Rhizobium strain having a form of nitrogenase that works only in the appropriate legume
host
C) each legume being found where the soil has only the Rhizobium specific to that legume
D) specific recognition between the chemical signals and signal receptors of the Rhizobium strain
and legume species
33) Rhizobia, actinomycetes, and cyanobacteria all share the common feature that they can
_____.
A) increase water uptake in plants
B) kill parasites in the soil
C) exist in extreme environments
D) fix atmospheric nitrogen
34) The earliest vascular plants on land had underground stems (rhizomes) but no roots. Water
and mineral nutrients were most likely obtained by _____.
A) diffusion through stomata
B) absorption by mycorrhizae
C) osmosis through the root hairs
D) diffusion across the cuticle of the rhizome
35) What major benefits do plants and mycorrhizal fungi receive from their symbiotic
relationship?
A) Plants receive enzymes, and fungi receive nitrogen and phosphorus.
B) Plants receive increased root surface area, and fungi receive digestive enzymes.
C) Fungi receive photosynthetic products in exchange for living in plant root nodules.
D) Plants receive nitrogen and phosphorus, and fungi receive photosynthetic products.
36) Hyphae form a covering over roots. These hyphae create a large surface area that helps to do
which of the following?
A) aid in absorbing minerals and ions
B) maintain cell shape
C) increase cellular respiration
D) anchor a plant
37) A plant developed a mineral deficiency after being treated with a fungicide. What is the most
probable cause of the deficiency?
A) Mineral receptor proteins in the plant membrane were not functioning.
B) Mycorrhizal fungi were killed.
C) Active transport of minerals was inhibited.
D) Proton pumps reversed the membrane potential.
38) We would expect the greatest difference in plant health between two groups of plants of the
same species, one group with mycorrhizae and one group without mycorrhizae, in an
environment _____.
A) where nitrogen-fixing bacteria are abundant
B) that has soil with poor drainage
C) in which the soil is relatively deficient in mineral nutrients
D) that is near a body of water, such as a pond or river
39) Which of the following is a primary difference between ectomycorrhizae and
endomycorrhizae?
A) Endomycorrhizae have thicker, shorter hyphae than ectomycorrhizae.
B) Ectomycorrhizae do not penetrate root cells, whereas endomycorrhizae grow into
invaginations of the root cell membranes.
C) Endomycorrhizae are more common than ectomycorrhizae.
D) There are no significant differences between ectomycorrhizae and endomycorrhizae.
40) Carnivorous plants have evolved mechanisms that trap and digest small animals. The
products of this digestion are used to supplement the plant’s supply of _____.
A) energy
B) carbohydrates
C) lipids and steroids
D) nitrogen and other minerals
41) Epiphytes are _____.
A) aerial vines common in tropical regions
B) plants that live in poor soil and digest insects to obtain nitrogen
C) plants that grow on other plants but do not obtain nutrients from their hosts
D) plants that have a symbiotic relationship with fungi
42) While hiking in a forest, you notice an unusual plant growing on the branches of a tree. What
will help you to determine if this plant is epiphytic or parasitic?
A) If the plant is green, it is epiphytic; if not, then it is parasitic.
B) The root of an epiphytic plant will be in the soil, but a parasitic plant will grow from the trunk
of a tree.
C) The roots of a parasitic plant will penetrate under the bark into the tree xylem, and the roots of
epiphytic plant will not.
D) The epiphytic plant will have large water collecting leaves, and the parasitic plant will not.