Deck 36: Plant Nutrition

Question 1

Which of the following elements is considered an essential micronutrient for plants?

A) zinc
B) potassium
C) hydrogen
D) platinum

Answer 1

A

Question 2

Which of the following macronutrients is rarely deficient?

A) carbon
B) hydrogen
C) oxygen
D) zinc

Answer 2

A

Question 3

A common consequence of nutrient deficiencies in plants is chlorosis. What is chlorosis?

A) It is death of the growing tips.
B) It is premature loss of leaves.
C) It is bursting of cells from excess water uptake due to an inability to clear chlorine from them.
D) It is yellowing of plant tissues due to a lack of chlorophyll.

Answer 3

D

Question 4

When tropical forests are cut for agriculture, they often do not produce highly productive crop growth. What is probably limiting the growth of a crop in the tropical forest?

A) sunlight
B) rainfall
C) soil nutrients
D) carbon dioxide

Question 5

Which of the following elements is considered an essential macronutrient for plants?

A) manganese
B) nickel
C) nitrogen
D) copper

Question 6

Which of the following elements is considered an essential micronutrient for plants?

A) phosphorus
B) silver
C) molybdenum
D) carbon

Question 7

Which of the following elements is considered an essential micronutrient for plants?

A) calcium
B) lithium
C) sulfur
D) nickel

Question 8

Which of the following elements is considered an essential macronutrient for plants?

A) oxygen
B) boron
C) lithium
D) molybdenum

Question 9

Which of the following statements does NOT describe an essential element?

A) An element with only one role in plant metabolism may still be essential.
B) An essential element is necessary for normal growth and reproduction.
C) Plant seeds in some cases contain enough of an essential element to sustain the adult plant.
D) An essential element may occasionally be functionally replaced by another element.

Question 10

Which of the following does NOT describe tropical rainforests?

A) Tropical rainforests are biologically diverse ecosystems.
B) Tropical rainforest soils have high acidity.
C) Minerals such as calcium and phosphorus are subject to leaching from the upper tropical rainforest soil level.
D) Tropical rainforest soils are extremely rich in nutrients.

Question 11

Which of the following nutrient deficiencies does NOT result in leaf chlorosis?

A) boron
B) iron
C) zinc
D) magnesium

Question 12

Experiments have shown that even if it is supplied by no other means, plants near the ocean can get enough of one of the following essential micronutrients from the air, and also from sweat from a person's hands. Which of the following is that macronutrient?

A) manganese
B) chlorine
C) magnesium
D) sodium

Question 13

What kind of process is called hydroponic culture?

A) growing plants in pure water mixed with carefully measured amounts of specific minerals
B) irrigating dry areas to improve mineral absorption by plants
C) growing plants in ponds and lakes to improve their access to water, allowing the plants to place more resources into the shoot system
D) irrigating dry areas to prevent crop plants from wilting

Question 14

Which of the following elements is considered an essential macronutrient for plants?

A) zinc
B) iron
C) nickel
D) carbon

Question 15

Which of the following elements is considered an essential micronutrient for plants?

A) gold
B) carbon
C) nitrogen
D) copper

Question 16

Which of the following comprise(s) more than 90% of the weight of plant tissues?

A) carbohydrates
B) water
C) carbon
D) nitrogen

Question 17

Imagine that you are a farmer who chose not to rotate your crops with soybeans even though the local extension agent recommended that you do so. Which deficiency symptom in your crops should indicate to you that the extension agent's advice was correct?

A) chlorosis and mottled or bronzed leaves
B) chlorosis in older leaves and stunted growth
C) pale green, rolled, or cupped leaves
D) burned leaf edges and curled, mottled, or spotted older leaves

Question 18

Which of the following disease symptoms would you expect to see in legumes grown in soil deficient of iron?

A) purplish veins and a lack of chlorophyll
B) chlorosis of plant tissues and mottled leaves
C) chlorosis of plant tissues and a lack of chlorophyll
D) purplish veins and mottled leaves

Question 19

Which of the following elements is NOT considered an essential micronutrient for plants in general, but is required by horsetails and perhaps some grasses such as wheat?

A) gold
B) boron
C) silicon
D) zinc

Question 20

You might infer from packages of commercial fertilizer that three of the following nutrients are most limiting to plant growth. What are those three?

A) carbon, nitrogen, and phosphorus
B) nitrogen, phosphorus, and potassium
C) hydrogen, phosphorus, and magnesium
D) iron, magnesium, and nitrogen

Question 21

A soil that tends to dry quickly compared to other soil types contains which of the following?

A) sand
B) humus
C) clay
D) silt

Question 22

Which of the following situations would be best for growing most plants?

A) a soil with very small air spaces
B) a soil with relatively large air spaces
C) a soil with air spaces filled almost entirely with water
D) a soil with various sizes of air spaces

Question 23

Which soil region is the top layer of surface litter, such as twigs and leaves?

A) A horizon
B) B horizon
C) C horizon
D) O horizon

Question 24

What are soil mineral particles that range from 0.02 - 0.002 mm in diameter called?

A) sand
B) humus
C) clay
D) silt

Question 25

Which of the following do mycorrhizae, present for most plant species, generally NOT help roots with the uptake of?

A) carbon
B) nitrogen
C) phosphate
D) water

Question 26

What are mycorrhizae?

A) connecting points between branching roots
B) symbiotic associations between a fungus and plant roots
C) specialized root hairs
D) localized swellings in plant roots filled with nitrogen-fixing bacteria

Question 27

What is a soil with roughly equal amounts of humus, silt, clay, and sand called?

A) a topsoil
B) a loam
C) a subsoil
D) a compost

Question 28

Which soil region tends to accumulate mineral ions but relatively little organic matter, and is generally penetrated by mature tree roots?

A) A horizon
B) B horizon
C) C horizon
D) O horizon

Question 29

Compare soils in the areas that receive heavy rainfalls with areas that are arid. What kind of soil is found in each?

A) acidic in wet; alkaline in arid
B) pH-neutral in wet; acidic in arid
C) alkaline in wet; acidic in arid
D) pH-neutral in wet; alkaline in arid

Question 30

Which soil region is the most fertile soil layer where the roots of most herbaceous plants are located?

A) A horizon
B) B horizon
C) C horizon
D) O horizon

Question 31

Which of the following best described the surfaces of clay particles in soil?

A) They often bear positively charged ions.
B) They release water to plants easily.
C) They often bear negatively charged ions.
D) They are generally hydrophobic.

Question 32

In which soils do most plants do best?

A) sandy soils
B) soils made mostly of humus
C) clay soils
D) loams

Question 33

Roots obtain cations through cation exchange. Which of the following do roots use to exchange for other cations from the soil?

A) Cl^-
B) K⁺
C) H⁺
D) H₂O

Question 34

What are soil mineral particles that are less than 0.002 mm in diameter called?

A) sand
B) humus
C) clay
D) silt

Question 35

What are soil mineral particles that range from 2.0 0.02 mm in diameter called?

A) sand
B) humus
C) clay
D) silt

Question 36

Which soil region extends to the underlying bedrock, and consists of mineral particles and rock fragments but generally no organic material?

A) A horizon
B) B horizon
C) C horizon
D) O horizon

Question 37

Research in Colorado's San Juan Mountains compared stands of lodgepole pine and Engelmann spruce with stands of trembling aspen. Compared to the other two, the aspen soil had all the following EXCEPT which?

A) higher temperatures
B) more nitrate
C) different arrays of organisms
D) more phosphorus

Question 38

What are soil particles that are decomposing organic matter called?

A) sand
B) humus
C) silt
D) clay

Question 39

Which of the following is most important for retaining water in soil for use by plants?

A) sand
B) humus
C) clay
D) silt

Question 40

Which of the following does NOT improve a plant's access to particular nutrients?

A) releasing amino acids into the soil
B) releasing carbohydrates into the soil
C) releasing enzymes into the soil
D) releasing carbon dioxide into the soil

Question 41

Studies of a soybean plant (Glycine max) and the bacterium Bradyrhizobium japonicum have shown that the tip of a root hair curls toward the bacteria as a response to which of the following?

A) a flavonoid released by soybean roots
B) nod gene products produced by soybean roots
C) nod gene products produced by the bacterium
D) nitrogen fixation by the bacterium

Question 42

In which form(s) can plants generally absorb nitrogen and make use of it?

A) nitrate only
B) both nitrate and ammonium ion
C) ammonium ion only
D) nitrogen molecule only

Question 43

Which of the following is mostly performed by bacteria living within the roots of plants in the legume family?

A) nitrification
B) ammonification
C) nitrogen cycling
D) nitrogen fixation

Question 44

What is the process in which NH₄⁺ is oxidized to NO₃^- called?

A) nitrification
B) ammonification
C) nitrogen cycling
D) nitrogen fixation

Question 45

In which process is the enzyme nitrogenase most directly involved?

A) nitrogen fixation
B) ammonification
C) nitrogen cycling
D) nitrification

Question 46

What are species of Rhizobium and Bradyrhizobium bacteria most directly associated with?

A) nitrification
B) nitrogen fixation
C) nitrogen cycling
D) ammonification

Question 47

Studies of a soybean plant (Glycine max) and the bacterium Bradyrhizobium japonicum have shown that after the bacteria enter the root, cells of the root cortex begin to divide. What is this a response to?

A) to a flavonoid released by soybean roots
B) to nod gene products produced by soybean roots
C) to nod gene products produced by the bacterium
D) to nitrogen fixation by the bacterium

Question 48

The most common limit to plant growth is the lack of which nutrient?

A) carbon
B) hydrogen
C) oxygen
D) nitrogen

Question 49

What will a mutant soybean plant that is unable to produce leghemoglobin most likely suffer from?

A) deficiency in magnesium
B) deficiency in potassium
C) deficiency in oxygen
D) deficiency in nitrogen

Question 50

Which of the following plants both parasitizes other plants and performs photosynthesis?

A) lady-of-the-night orchid
B) mistletoe
C) cobra lily
D) dodder

Question 51

Which of these statements describes bacteroids?

A) specialized nitrifying bacteria
B) small buds from ammonifying bacteria
C) specialized bacteria that help some plant roots absorb phosphorus
D) enlarged and immobilized nitrogen-fixing bacteria

Question 52

What are root nodules?

A) connecting points between branching roots
B) localized swellings in plant roots filled with nitrogen-fixing bacteria
C) specialized root hairs
D) symbiotic associations between a fungus and plant roots

Question 53

What is the process of adding hydrogen to N₂, creating NH₃ and eventually NH₄⁺, with a substantial input of ATP called?

A) nitrogen fixation
B) ammonification
C) nitrogen cycling
D) nitrification

Question 54

What is the process of producing NH₄⁺ from decaying organic material called?

A) nitrification
B) ammonification
C) nitrogen cycling
D) nitrogen fixation

Question 55

Which of the following in excess irreversibly inhibits the enzyme nitrogenase?

A) O₂
B) NO₃
C) N₂
D) CO₂

Question 56

Which of the following is converted inside root cells into its product, which is then rapidly used to synthesize organic molecules?

A) NH₄⁺ is converted to NO₃
B) N₂ is converted to NO₃
C) NO₃
D) NH is converted to NH₄⁺.

Question 57

Farmers often grow legumes such as soybeans every few years and plow much of the plant parts into the soil. What does this practice mainly serve?

A) to replenish the soil with useful forms of carbon
B) to replenish the soil with useful forms of nitrogen
C) to replenish the soil with useful forms of phosphorus
D) to replenish the soil with useful forms of oxygen

Question 58

What are animals trapped and digested by "carnivorous" plants such as the cobra lily used as?

A) primarily as an energy supplement during winter months
B) primarily as a carbon source for the plant
C) primarily as a nutrient supplement in nutrient-deficient environments
D) primarily as food for bacteria and fungi that grow symbiotically with the plant roots

Question 59

What do the haustorial roots of dodders and other non-photosynthetic, parasitic plants rob the host plant of?

A) sugars and water
B) water and minerals
C) sugars and minerals
D) sugars, minerals, and water

Question 60

What is leghemoglobin, which contains an iron-containing heme group, used for?

A) to remove O₂ from roots
B) to produce H₂O from O₂
C) to deliver O₂ to bacteroids
D) to transport O₂ in the xylem

Question 61

Choose the appropriate category of general plant nutritional requirement for each element given below.
a.nonmineral macronutrient
b.mineral macronutrient
c.micronutrient
d.not generally considered an essential nutrient
oxygen

Question 62

Choose the appropriate category of general plant nutritional requirement for each element given below.
a.nonmineral macronutrient
b.mineral macronutrient
c.micronutrient
d.not generally considered an essential nutrient
nickel

Question 63

What is the potential significance of root exudates?

Question 64

The snow plant lacks chlorophyll and does not have haustorial leaves.

Question 65

Dodders develop haustorial leaves that penetrate deep into the host plant and tap into its vascular tissues.

Question 66

What are the most common deficiency symptoms and what process is most affected?

Question 67

What kind of plants are epiphytes?

A) Plants that are not parasites but that do grow on other plants instead of the soil.
B) Plants that trap animals and digest them.
C) Plants that deal with nutrient-deficient soil by growing a large, netlike mesh of roots through several layers of the soil.
D) Parasitic plants that use haustoria roots to obtain nutrients and food directly from other plants.

Question 68

Explain why few plants can grow well in clay soils, even when water content is high.

Question 69

Choose the appropriate category of general plant nutritional requirement for each element given below.
a.nonmineral macronutrient
b.mineral macronutrient
c.micronutrient
d.not generally considered an essential nutrient
gold

Question 70

Why might a soil that has a sufficient concentration of a mineral element, such as calcium, not have sufficient availability of the element to maximize plant growth rates?

Question 71

Mycorrhizae are crucial symbiotic associations between a fungus and the stems of a plant.

Question 72

Choose the appropriate category of general plant nutritional requirement for each element given below.
a.nonmineral macronutrient
b.mineral macronutrient
c.micronutrient
d.not generally considered an essential nutrient
manganese

Question 73

Nutrients clearly limit the growth of plants. Explain four ways that plants have adapted to increase access to nutrients and what limits the association from becoming more common.

Question 74

Describe how losing leaves in the autumn can affect plant nutrient requirements, and how plants handle this issue.

Question 75

In temperate forests, many mosses and lichens are epiphytes.

Question 76

Trace the route of most mineral ions from entering a plant to being used for the plant's metabolic reactions.

Question 77

What is cation exchange in plant roots?

Question 78

There are many potential ways to reduce the amount of inorganic fertilizer that is applied to cropland. If you were to make recommendations on the application of an inorganic fertilizer to a crop, what are some of the variables and processes you would consider?

Question 79

Explain hydroponics and its importance in studies of plant nutrition.

Question 80

Why are hydroponics used in mineral nutrition experiments examining essential elements?