Deck 37: Plant Nutrition and Soils

Question 1

Insectivorous plants such as the Venus flytrap,pitcher plant,and bladderworts often grow in

A)alkaline soil.
B)sandy soil.
C)clay soil.
D)marshes.
E)acidic soils.

Answer 1

E

Question 2

Which of the following statements about plants grown in hydroponic culture is true?

A)They no longer need to transport water through their xylem.
B)They cannot be used for commercial purposes.
C)They rarely get enough micronutrients.
D)They are unable to photosynthesize.
E)They are suspended with their roots in a nutrient solution.

Answer 2

E

Question 3

Plants can remove harmful chemicals from the soil by the process of

A)glandular secretion by leaves.
B)CO₂ activation.
C)phytoremediation.
D)fertilization.
E)root nodule formation.

Answer 3

C

Question 4

A deficiency of ammonia would inhibit the production of which of the following molecules?

A)proline and alanine
B)starch
C)short chain fatty acids
D)glucose and fructose
E)long chain fatty acids

Question 5

The effects of elevated atmospheric CO₂ concentrations

A)have the potential to alter the nutritional status of plants.
B)have the potential to allow herbivores to eat less plant matter.
C)have no effect on nutrient levels found in plant leaves.
D)allow the plant to use O₂ more efficiently in photosynthesis.
E)cause an increase in rubisco production.

Question 6

Which of the following is most limiting for plant growth,especially in relation to the plant's carbon uptake?

A)phosphorous
B)potassium
C)nitrogen
D)calcium
E)magnesium

Question 7

During the initiation of nitrogen-fixation nodules,a host plant with genetic mutations releases altered forms of flavonoids.What is the likely consequence of this?

A)Infection threads will grow in the wrong direction.
B)More nodules will form than necessary.
C)The bacteria will not produce any Nod factors.
D)Nodules will be misshapen.
E)The bacterial will produce higher levels of Nod factors.

Question 8

During the initiation of nitrogen-fixation nodules,the Rhizobium bacteria release what type of molecules to signal the host plant?

A)sugars
B)proteins
C)transcription factors
D)flavonoids
E)Nod factors

Question 9

Although symbiotic relationships between nitrogen-fixing bacteria and plants are rare,many plants have symbiotic relationships with

A)other plants.
B)nematode worms in the soil.
C)filamentous algae.
D)mycorrhizal fungi in the soil.
E)soil insects.

Question 10

A primary advantage of using integrated nutrient management compared to inorganic chemical fertilizers is that

A)less organic fertilizer is needed than chemical fertilizers.
B)only organic fertilizers contain micronutrients.
C)organic fertilizers release nutrients more slowly.
D)chemical fertilizers are not soluble in water.
E)chemical fertilizers break down very slowly.

Question 11

Inserting a cloned gene for a plasma membrane transporter into crop plants could lead to

A)the ability of a plant to produce its own micronutrients.
B)extra uptake of minerals that would fortify the crop for human consumption.
C)the evolution of nodule-formation on the crop plant.
D)elevated CO₂ levels in the atmosphere.
E)plants taking up enough minerals that they no longer need to photosynthesize.

Question 12

Which of the following is required by plants in the smallest quantity?

A)boron
B)potassium
C)phosphorus
D)nitrogen
E)sulfur

Question 13

The habitats most favorable for the growth of legumes in symbiosis with nitrogen-fixing bacteria are

A)potassium-poor soils.
B)phosphorus-poor soils.
C)manganese-poor soils.
D)calcium-poor soils.
E)nitrogen-poor soils.

Question 14

Certain plants have been genetically modified to secrete citrate,which helps

A)make the phosphate in soils more soluble.
B)plants make necessary micronutrients.
C)reveal mineral deficiencies in a plant.
D)make hydroponic growth possible.
E)plants add metals to the soil in which they are growing.

Question 15

A deficiency in a plant micronutrient

A)is less serious than a deficiency in a macronutrient.
B)makes that plant susceptible to herbivores.
C)can have a severe effect on plant growth.
D)results in no visible symptoms.
E)has no impact on the agriculture of a region.

Question 16

The Nod factor is an important component of

A)the formation of the digestive enzymes of carnivorous plants.
B)legume-bacterial interactions.
C)mycorrhizal-terrestrial plant interactions.
D)the Calvin Cycle.
E)trichloroethylene metabolism.

Question 17

Natural communities recycle nutrients,but cultivated communities often require an input of mineral nutrients due to losses through

A)erosion.
B)humus.
C)nitrogen fixation.
D)crop rotation.
E)iron accumulation.

Question 18

Trichloroethylene (TCE)is toxic to humans because it

A)depletes nitrogen from soils.
B)is carcinogenic.
C)contains heavy metals.
D)prevents CO₂ production by plants.
E)causes a decrease in the yield of crop plants.

Question 19

Carnivorous plants evolved because which of the following nutrients is often extremely limited in their habitats?

A)carbon
B)CO₂
C)O₂
D)nitrogen
E)iron

Question 20

Heavy metals in contaminated soils can be taken up by hyperaccumulating plants.Lead and cadmium taken up this way are often accumulated in the plants'

A)rhizomes.
B)trichomes.
C)stomates.
D)sclerenchyma.
E)root nodules.

Question 21

Which of these is considered a potentially dangerous heavy metal contaminant in soil?

A)cadmium
B)iron
C)copper
D)molybdenum
E)zinc

Question 22

What makes a mineral element essential for plant growth?

A)It is part of typical chemical fertilizers.
B)It can only be found in organic fertilizers.
C)If it is missing,the plant cannot grow or reproduce normally.
D)As its concentration increases,the plant grows more.
E)It contributes to the solute potential of the plant.

Question 23

Mycorrhizae are especially effective in helping plant roots uptake

A)nitrogen.
B)phosphorus.
C)potassium.
D)iron.
E)magnesium.

Question 24

Why is it beneficial to plants that soil particles have negatively-charged surfaces?

A)It helps maintain the water potential of the soil.
B)They attract positively-charged ions and prevent them from being washed deep into the soil.
C)Negatively-charged ions are pushed towards the roots.
D)Toxic metals are trapped and kept away from the plants.
E)They capture negatively-charged ions.

Question 25

Humus often enhances the water and nutrient-retaining properties of topsoil.Which of the following might increase the humus content of a soil? Check all that apply.

A)mushroom compost
B)leaf litter
C)ground limestone
D)phosphate fertilizer
E)fish meal

Question 26

A parasitic plant without chlorophyll is likely to lack leaves.

Question 27

When plants are grown in hydroponic culture,their roots are suspended in an aerated solution.Why is the solution aerated? Check all that apply.

A)Both the light-dependent and the light-independent reactions of photosynthesis require oxygen.
B)Oxygen is necessary for the root cells to produce ATP.
C)Without oxygen,membrane transport in the roots would be impaired.
D)A lack of oxygen would cause the water potential within the roots to decrease.
E)Without oxygen,the xylem would stop flowing.

Question 28

A magnesium deficiency would impact the light-independent reactions but not the light-dependent reaction of photosynthesis.

Question 29

Which of these insectivorous plants does not use an active trapping mechanism?

A)pitcher plants
B)Venus flytraps
C)sundews
D)the aquatic waterwheel
E)bladderworts

Question 30

In several studies of plant responses to elevated CO₂ concentrations in the atmosphere,scientists often found that the stimulation of growth gradually diminished because

A)more photorespiration occurred.
B)C₃ plants were replaced with C₄ plants.
C)the soil did not contain sufficient nitrogen and other nutrients to support the enhanced growth.
D)the plants could not store the extra biomass.
E)weedy plants took over the experimental plots.

Question 31

In magnesium-deficient plants the older leaves show more severe symptoms of chlorosis which is a yellowing of the leaves than younger leaves.What is the best explanation?

A)There is more time for the symptoms to develop in older leaves.
B)Chlorophyll is transported from the older leaves to the younger leaves.
C)Magnesium is more soluble in younger leaves.
D)Scarce magnesium is removed from older leaves and translocated to support younger,more active leaves.
E)Older leaves need less chlorophyll.

Question 32

Why do nitrogen-fixation nodules contain large amounts of leghemoglobin?

A)It helps transport oxygen to the bacteria.
B)The nitrogenase enzyme interacts with the iron in the leghemoglobin.
C)The leghemoglobin helps break the triple bond of N₂.
D)It stimulates the Nod factors.
E)It prevents carbon dioxide from inhibiting the nitrogenase enzyme.

Question 33

Inside nitrogen-fixing nodules,one N₂ molecule is converted into two

A)N)
B)NO.
C)NO₂.
D)NO₃.
E)NH₃.

Question 34

A plant with 80 available ATP could produce 10 molecules of NH₃.

Question 35

When legumes with nitrogen-fixation nodules are given chemical fertilizers with high nitrogen concentrations,they abandon support of the nodules and end the symbiosis.Why?

A)The mineral nutrients inhibit nitrogenase activity.
B)Nitrogen gas is no longer available in the soil.
C)The plant can conserve valuable energy sources by terminating the symbiotic relationship.
D)The dissolved chemical nutrients are toxic to Rhizobium bacteria.
E)Dissolved nitrogen uncurls the root hairs,releasing the nodule.

Question 36

During the initiation of nitrogen-fixation nodules,how do the Rhizobium bacteria enter into the cortex of the root?

A)through the plasmadesmata of the root hairs
B)via the apoplastic pathway
C)using proton pumps
D)through a membrane tube called an infection thread
E)by repeated cell divisions

Question 37

If increased CO₂ concentrations result in plant tissue that is less nutritious,which of these is not a potential consequence for insect herbivores?

A)They must eat more tissue.
B)Their development may be slowed.
C)They grow fatter because their diet has more carbohydrates.
D)They use up more energy trying to eat for food.
E)Their reproductive cycles may be disrupted because their rate of growth changes.

Question 38

A plant cell with 64 available ATP molecules could split how many N₂ molecules with the assistance of nitrogenase?

A)2
B)4
C)16
D)32
E)64

Question 39

Blocking the proton pumps in a root would result in a more negative membrane potential and an increase in K⁺ uptake.

Question 40

In acidic soils or in habitats subjected to prolonged acid rain,what element is often released from rocks that is toxic to many plants?

A)iron
B)chlorine
C)molybdenum
D)selenium
E)aluminum

Question 41

Saline soils have a higher water potential than plant roots.

Question 42

Which of the following statements about plant macronutrients is/are true? Check all that apply.

A)They approach or exceed 1% of a healthy plant's dry weight.
B)They reduce the need for CO₂ during photosynthesis.
C)A deficiency in any one can have severe effects on a plant's growth.
D)They can have important implications for human nutrition.
E)The ability of the plants to take up minerals is affected by soil pH.

Question 43

Which of the following is a natural process of plants that can be used by humans to remove toxins from soils? Check all that apply.

A)secretion of a substance from the roots that breaks down the toxic chemical
B)"storage" of a toxic chemical in plant tissues,which are then removed from the site
C)root pressure pushing toxins from deep in the soil towards the surface
D)physiological breakdown of the chemical into harmless products
E)transport of toxins absorbed by the roots into the shoots,where they can be collected more easily

Question 44

In lab,you are studying the long term effects of elevated carbon dioxide levels on photosynthesis in C3 and C4 plants.The C3 and C4 plants are growing in separate closed chambers.Both chambers are constantly given elevated but equal amounts of carbon dioixde.Which of the following are likely results of this experiment? Check all that apply.

A)There would be a decrease in O₂ levels in both chambers.
B)There would be an increase in O₂ levels in both containers.
C)Both the C3 and the C4 plants would show equal gains in biomass.
D)The C4 plants would gain more biomass relative to the C3 plants.
E)The C3 plants would gain more biomass relative to the C4 plants.

Question 45

As global temperatures increase,evidence suggests that ribulose 1,5-biphosphate carboxylase/oxygenase (rubisco)is likely to denature and photosynthesis rates will decrease.

Question 46

A soil sample with a OH^- concentration of 10^-9 M may also have high levels of aluminum.

Question 47

Most parasitic plants like other land plants have mycorrhizal symbionts.