Question 1

Recall that leaves form in distinct arrangements (whorled, opposite, or alternate)  on the stems of vascular plants. How might chemical factors cause new leaves to form in these particular patterns?

Accepted Answer

A)  Leaf primordia drain auxin from neighboring cells, with new primordia forming where auxin in the meristem surface is at the highest concentration.
B)  Leaf primordia secrete chemical activators that promote the formation of leaves nearby.
C)  Mature leaves secrete chemical inhibitors that prevent the formation of leaves nearby.
D)  Mature leaves secrete chemical activators that promote the formation of leaves nearby.E) B) and C)
F) A) and D)

Question 2

Phytochrome prevents seeds of some plants from germinating when they are in deep shade by the:

Accepted Answer

A)  absorption of far-red wavelengths by chlorophyll.
B)  absorption of red wavelengths by Pr.
C)  absorption of far-red wavelengths by Pfr.
D)  slow conversion of Pfr to Pr in the dark.
E)  slow conversion of Pr to Pfr in the dark.F) None of the above
G) B) and C)

Question 3

As trees get larger and the number of leaves increases, transpiration rates rise and demand for water increases. How do mature plant stems meet this added demand for water?

Accepted Answer

A)  Cells of the xylem continue to divide and produce more cells that transport water.
B)  Vascular cambium continues to divide, and cells of its inner surface differentiate to form additional secondary xylem cells.
C)  Cells of secondary phloem adjacent to the vascular cambium differentiate into xylem cells.
D)  Cells present in the pith closest to the xylem differentiate into xylem cells.E) None of the above
F) All of the above

Question 4

In order for a root to branch, new apical meristem must form from the _____, a single layer of cells inside the endodermis of the root.

Accepted Answer

The answer of In order for a root to branch,...

Question 5

You notice that your houseplants are all growing toward the light from your window. This indicates that their stems display:

Accepted Answer

A)  positive gravitropism.
B)  positive thermotropism.
C)  positive phototropism.
D)  negative phototropism.
E)  negative gravitropism.F) A) and C)
G) A) and B)

Question 6

Plants that are "creepers" grow along the ground, with vertical leaves or shoot systems attached at each node of the horizontal stem. Such plants often lack secondary growth; how, then, do they supply water and nutrients to a growing number of leaves as the plant spreads?

Accepted Answer

A)  They make more efficient use of the primary vasculature in the stem.
B)  Even though no new vasculature can be produced, the existing xylem and phloem in the stem can increase in size and transport capacity.
C)  Each stem node initiates its own root meristem, bypassing the need for increasing water and nutrient transport within the prostrate stem.
D)  Some lateral branches from the prostrate stem become negatively gravitropic and take on root meristem identity.E) A) and D)
F) B) and D)

Question 7

In general, when a cell or tissue type has to serve multiple functions that each contribute to fitness, natural selection is constrained from optimizing that tissue of cell type for any one function. With this concept in mind, fill in the blanks in the sentence below with the appropriate term: poor, positive, negative. The terms may be used once, more than once, or not at all.
"In angiosperms you would expect a _____ correlation between the diameter of the water conducting conduits and the mechanical strength of the wood. In gymnoperms you would expect the correlation to be _____."

Accepted Answer

The answer of In general, when a cell or tissue...

Question 8

Exposure to light and gravity will cause a root to grow downward into the soil.

Accepted Answer

A) True 
 B)False

Question 9

If you were to dissect a root, the layers from outside to inside would be:

Accepted Answer

A)  epidermis  cortex  endodermis  phloem  xylem.
B)  cortex  epidermis  phloem  endodermis  xylem.
C)  epidermis  cortex  endodermis  xylem  phloem.
D)  endodermis  cortex  epidermis  phloem  xylem.
E)  epidermis  endodermis  cortex  phloem  xylem.F) B) and E)
G) A) and C)

Question 10

Garner and Allard could not have done the Maryland Mammoth experiments in the tropics because:

Accepted Answer

A)  daylength is relatively constant through the year and never below the critical threshold.
B)  daylength is relatively constant through the year and never above the critical threshold.
C)  tobacco is day-neutral.
D)  temperatures in the tropics are too high for tobacco to flower.E) None of the above
F) A) and B)

Question 11

Imagine that angiosperms were suddenly unable to control their time of flowering. What would be the result?

Accepted Answer

A)  Because angiosperms have long life cycles, there would be little effect; if plants failed to reproduce one year, they will likely compensate by producing more flowers the following year.
B)  There would likely be little effect because angiosperm pollinators are present year round (i.e., insects in the spring/summer and birds in the fall/winter) .
C)  There would likely be little effect because angiosperm pollen is able to survive on plant surfaces for months at a time.
D)  None of the answer options is correct.E) A) and C)
F) A) and D)

Question 12

Which of the following were key events in the evolution of vascular plant leaves?

Accepted Answer

A)  the conversion of stems (or branches) to flattened structures
B)  the development of apical meristem identity genes
C)  the development of leaf meristem cells
D)  the development of leaf identity genesE) None of the above
F) A) and D)

Question 13

Within each "unit" composing a shoot of a vascular plant, you would observe leaves attached at the _____, and a large stretch of stem without leaves at the _____.

Accepted Answer

A)  node; shoot apical meristem
B)  node; internode
C)  shoot apical meristem; node
D)  internode; nodeE) B) and C)
F) None of the above

Question 14

The development of axillary buds is under the control of a single hormone, cytokinin.

Accepted Answer

A) True 
 B)False

Question 15

Roots are capable of which types of growth?

Accepted Answer

A)  primary growth only
B)  secondary growth only
C)  both primary and secondary growth
D)  apical growth only
E)  lateral growth onlyF) A) and B)
G) C) and E)

Question 16

At the tip of each branch, the _____ surround(s)  the shoot apical meristem.

Accepted Answer

A)  bundle sheath
B)  leaf primordia
C)  flower bud
D)  node
E)  internodeF) B) and E)
G) B) and D)

Question 17

Photoperiodism depends on which of the following factors?

Accepted Answer

A)  the activation of photoreceptors
B)  daily fluctuations of auxin
C)  the accumulation and stabilization of auxin
D)  the inhibition of phytochromeE) A) and C)
F) C) and D)

Question 18

You are surveying a crop and find that insects have eaten the shoot apical meristems of all the plants, but none of the axillary buds have started to grow out. In addition, you noticed many of the plants are showing signs of nitrogen deficiency and/or wilting. You sample axillary buds from these plants for analysis and hypothesize that you will find:

Accepted Answer

A)  low levels of both cytokinin and strigolactone.
B)  high levels of both cytokinin and strigolactone.
C)  high levels of cytokinin but low levels of strigolactone.
D)  low levels of cytokinin but high levels of strigolactone.E) All of the above
F) B) and D)

Question 19

The vascular cambium:

Accepted Answer

A)  may be one cell thick.
B)  can divide only toward the center of the stem.
C)  forms a continuous layer.
D)  can divide to increase in circumference.
E)  may be one cell thick, forms a continuous layer, and can divide to increase in circumference.F) B) and C)
G) C) and E)

Question 20

Collectively, what did the work of Charles Darwin, Francis Darwin, and Frits Went demonstrate about phototropism in plants?

Accepted Answer

A)  A chemical signal is produced in shoot tips in response to light.
B)  A chemical signal is produced in shoot stems in response to light.
C)  Cells exposed to a chemical signal produced by light will grow toward the light.
D)  Cells exposed to a chemical signal produced by light will not grow toward the light.E) A) and B)
F) A) and C)

Exam 31: Plant Growth and Development

Within each "unit" composing a shoot of a vascular plant, you would observe leaves attached at the _, and a large stretch of stem without leaves at the _.

Correct Answer
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Correct Answer
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The vascular cambium:

Correct Answer
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Imagine that angiosperms were suddenly unable to control their time of flowering. What would be the result?

Correct Answer
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Photoperiodism depends on which of the following factors?

Correct Answer
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Exposure to light and gravity will cause a root to grow downward into the soil.

Correct Answer
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Plants that are "creepers" grow along the ground, with vertical leaves or shoot systems attached at each node of the horizontal stem. Such plants often lack secondary growth; how, then, do they supply water and nutrients to a growing number of leaves as the plant spreads?

Correct Answer
verified

You notice that your houseplants are all growing toward the light from your window. This indicates that their stems display:

Correct Answer
verified

Collectively, what did the work of Charles Darwin, Francis Darwin, and Frits Went demonstrate about phototropism in plants?

Correct Answer
verified

Phytochrome prevents seeds of some plants from germinating when they are in deep shade by the:

Correct Answer
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Roots are capable of which types of growth?

Correct Answer
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Which of the following were key events in the evolution of vascular plant leaves?

Correct Answer
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At the tip of each branch, the _____ surround(s) the shoot apical meristem.

Correct Answer
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Correct Answer
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Garner and Allard could not have done the Maryland Mammoth experiments in the tropics because:

Correct Answer
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If you were to dissect a root, the layers from outside to inside would be:

Correct Answer
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Recall that leaves form in distinct arrangements (whorled, opposite, or alternate) on the stems of vascular plants. How might chemical factors cause new leaves to form in these particular patterns?

Correct Answer
verified

In order for a root to branch, new apical meristem must form from the _____, a single layer of cells inside the endodermis of the root.

Correct Answer
verified

As trees get larger and the number of leaves increases, transpiration rates rise and demand for water increases. How do mature plant stems meet this added demand for water?

Correct Answer
verified

The development of axillary buds is under the control of a single hormone, cytokinin.

Correct Answer
verified

Exam 31: Plant Growth and Development

Within each "unit" composing a shoot of a vascular plant, you would observe leaves attached at the _____, and a large stretch of stem without leaves at the _____.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The vascular cambium:

Correct AnswerverifiedShow Answer

Imagine that angiosperms were suddenly unable to control their time of flowering. What would be the result?

Correct AnswerverifiedShow Answer

Photoperiodism depends on which of the following factors?

Correct AnswerverifiedShow Answer

Exposure to light and gravity will cause a root to grow downward into the soil.

Correct AnswerverifiedShow Answer

Plants that are "creepers" grow along the ground, with vertical leaves or shoot systems attached at each node of the horizontal stem. Such plants often lack secondary growth; how, then, do they supply water and nutrients to a growing number of leaves as the plant spreads?

Correct AnswerverifiedShow Answer

You notice that your houseplants are all growing toward the light from your window. This indicates that their stems display:

Correct AnswerverifiedShow Answer

Collectively, what did the work of Charles Darwin, Francis Darwin, and Frits Went demonstrate about phototropism in plants?

Correct AnswerverifiedShow Answer

Phytochrome prevents seeds of some plants from germinating when they are in deep shade by the:

Correct AnswerverifiedShow Answer

Roots are capable of which types of growth?

Correct AnswerverifiedShow Answer

Which of the following were key events in the evolution of vascular plant leaves?

Correct AnswerverifiedShow Answer

At the tip of each branch, the _____ surround(s) the shoot apical meristem.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Garner and Allard could not have done the Maryland Mammoth experiments in the tropics because:

Correct AnswerverifiedShow Answer

If you were to dissect a root, the layers from outside to inside would be:

Correct AnswerverifiedShow Answer

Recall that leaves form in distinct arrangements (whorled, opposite, or alternate) on the stems of vascular plants. How might chemical factors cause new leaves to form in these particular patterns?

Correct AnswerverifiedShow Answer

In order for a root to branch, new apical meristem must form from the _____, a single layer of cells inside the endodermis of the root.

Correct AnswerverifiedShow Answer

As trees get larger and the number of leaves increases, transpiration rates rise and demand for water increases. How do mature plant stems meet this added demand for water?

Correct AnswerverifiedShow Answer

The development of axillary buds is under the control of a single hormone, cytokinin.

Correct AnswerverifiedShow Answer

Within each "unit" composing a shoot of a vascular plant, you would observe leaves attached at the _, and a large stretch of stem without leaves at the _.

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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