Deck 34: Leaf Structure and Function

Question 1

The area of the angle between the stem and the leaf stalk is referred to as the:

A) axil.
B) blade.
C) petiole.
D) stipule.
E) trichome.

Answer 1

A

Question 2

Figure 34-1
Use the figure to answer the corresponding question(s).
The leaf arrangement illustrated in Figure 34-1 is:

A) pinnate.
B) alternate.
C) compound.
D) whorled.
E) parallel.

Answer 2

B

Question 3

Figure 34-2
Use the figure to answer the corresponding question(s).
The organization of tissues in Figure 34-2 is characteristic of:

A) a stem.
B) a spine.
C) a leaf.
D) a bulb.
E) a bud scale.

Answer 3

C

Question 4

Floating leaves of aquatic plants have:

A) stomata only on the lower epidermis.
B) stomata only on the upper epidermis.
C) stomata on both the lower and upper epidermis.
D) no stomata on the epidermis.
E) stomata only within the mesophyll.

Question 5

Figure 34-2
Use the figure to answer the corresponding question(s).
The middle portion of a leaf that is sandwiched between the upper and lower epidermis is called the:

A) mesoderm.
B) middle lamella.
C) mesophyte.
D) bundle sheath.
E) mesophyll.

Question 6

Figure 34-2
Use the figure to answer the corresponding question(s).
Refer to Figure 34-2.The structure labeled __________ is responsible for the transport of dissolved sugars.

A) 4
B) 5
C) 6
D) 7
E) 9

Question 7

The primary function of spongy mesophyll is:

A) photosynthesis.
B) transpiration.
C) to allow diffusion of gases.
D) transport of substances.
E) transport of water.

Question 8

The only epidermal cells with chloroplasts are:

A) stomata.
B) stoma.
C) parenchyma.
D) guard cells.
E) all of these.

Question 9

Figure 34-2
Use the figure to answer the corresponding question(s).
Mesophyll cells are:

A) arranged tightly together.
B) separated by intercellular spaces.
C) responsible for the opening and closing of stomata.
D) devoid of chloroplasts.
E) covered by a waxy cuticle, which they secrete.

Question 10

Photosynthesis occurs chiefly in the leaf's:

A) epidermis.
B) bundle sheath extensions.
C) mesophyll.
D) trichomes.
E) vascular bundles.

Question 11

The broad, flat part of a leaf is called the __________, while the stalk that attaches the leaf to the stem is called the __________.

A) stipule; petiole
B) blade; stipule
C) stipule; axil
D) petiole; axil
E) blade; petiole

Question 12

Stomata are:

A) waxy layers that cover leaves.
B) openings in the leaf epidermis.
C) extensions of bundle sheaths.
D) particularly numerous on the upper epidermis.
E) guarded by two stipule cells.

Question 13

Figure 34-1
Use the figure to answer the corresponding question(s).
The cuticle consists of:

A) cellulose.
B) lignin.
C) hemicellulose.
D) starch.
E) cutin.

Question 14

Figure 34-1
Use the figure to answer the corresponding question(s).
The type of leaf arrangement in Figure 34-1 is characteristic of:

A) ashes.
B) maples.
C) catalpas.
D) beeches.
E) buckeyes.

Question 15

Figure 34-1
Use the figure to answer the corresponding question(s).
Which of the following statements does not describe the leaf epidermis?

A) The cells all contain chloroplasts and photosynthesize.
B) Some of the cells are modified to form trichomes.
C) The cells are covered by a waxy cuticle.
D) The cells are relatively transparent.
E) It contains stomata, each of which is flanked by two guard cells.

Question 16

Leaflike outgrowths at the base of the leaf stalk are referred to as:

A) axils.
B) blades.
C) lamina.
D) petioles.
E) stipules.

Question 17

Which of the following statements concerning trichomes is FALSE?

A) They reduce water loss from leaf surface.
B) They deter herbivores.
C) They excrete excess salts absorbed from salty soil.
D) They are hairlike structures on the epidermis.
E) They facilitate gas exchange.

Question 18

Guard cells are often associated with __________, special epidermal cells that provide a reservoir of water and ions.

A) companion cells
B) cuticle cells
C) cork cells
D) sclerenchyma cells
E) subsidiary cells

Question 19

Compound leaves have:

A) parallel veins instead of netted veins.
B) alternate leaf attachment instead of opposite leaf attachment.
C) palmately netted leaves instead of pinnately netted leaves.
D) two or more leaflets instead of a single blade.
E) many leaves per plant instead of a single leaf per plant.

Question 20

Leaves:

A) represent a fairly small fraction of the overall metabolic budget for a plant.
B) depend on the roots to supply CO₂.
C) are the main photosynthetic organ of most plants.
D) are the main site of water uptake in plants.
E) prevent CO₂ and O₂ from entering the plant.

Question 21

During the photosynthetic process, __________ diffuses into the leaf, while __________ diffuses out of the leaf.

A) carbon dioxide; oxygen
B) oxygen; carbon dioxide
C) oxygen; water vapor
D) water vapor; carbon dioxide
E) water vapor; oxygen

Question 22

The process by which water is lost by evaporation from plant parts is known as:

A) vaporization.
B) photosynthesis.
C) guttation.
D) transpiration.
E) abscission.

Question 23

__________ is responsible for water movement in plants.

A) Guttatiion
B) Evaporation
C) Transpiration
D) Photosynthesis
E) Cellular respiration

Question 24

Photosynthesis reduces the leaf's internal concentration of:

A) hydrogen.
B) carbon dioxide.
C) nitrogen.
D) oxygen.
E) sugars and starches.

Question 25

Before a stoma opens:

A) the level of carbon dioxide inside the leaf increases.
B) potassium ions are actively transported out of guard cells.
C) potassium ions are actively transported into guard cells.
D) the turgor pressure inside the guard cells decreases.
E) water moves by osmosis out of the guard cells.

Question 26

Monocot leaves typically have:

A) alternately palmate venation.
B) netted venation.
C) parallel venation.
D) alternately pinnate venation.
E) no venation.

Question 27

If a plant were placed in continual darkness, it would continue to open and close its stomata at approximately the same time each day.This phenomenon is governed by:

A) annual rhythms.
B) floral clocks.
C) transpiration.
D) temporal mechanisms.
E) circadian rhythms.

Question 28

What structures provide support to the leaf and prevent it from collapsing under its own weight?

A) palisade mesophyll and spongy mesophyll
B) guard cells and the lower epidermis
C) bundle sheaths and bundle sheath extensions
D) cuticle and the upper epidermis
E) trichomes and stipules

Question 29

Which of the following is most important in stomatal closing?

A) declining sucrose concentrations
B) rising sucrose concentrations
C) rising potassium concentrations
D) declining potassium concentrations
E) declining chloride concentrations

Question 30

The process of photosynthesis involves the conversion of:

A) oxygen and water into sugar.
B) sugar into starches and cellulose.
C) oxygen and sugar into water.
D) carbon dioxide and water into sugar.
E) sugar and water into lipids.

Question 31

The rate of transpiration increases under all of the following conditions except:

A) increased wind.
B) increased humidity.
C) increased temperature.
D) presence of sunlight.
E) an increase in dry air.

Question 32

The stomatal opening and closing are under the control of __________.

A) ethylene
B) cytokinins
C) auxins
D) abscisic acid
E) gibberellins

Question 33

Opening of the stomata:

A) occurs during prolonged periods of drought.
B) occurs when there is a high concentration of carbon dioxide in the leaf.
C) is under hormonal control.
D) is triggered by darkness.
E) is controlled by the changes in shape of the companion cells.

Question 34

Which structure or structures function to open and close the stomata?

A) cuticle
B) mesophyll
C) palisade cells
D) guard cells
E) chloroplasts

Question 35

Eudicot leaves typically have:

A) alternately palmate venation.
B) netted venation.
C) parallel venation.
D) alternately pinnate venation.
E) no venation.

Question 36

__________ colored light triggers stomatal opening.

A) Red
B) Blue
C) Orange
D) Green
E) Yellow

Question 37

Which of the following is not true of monocot leaves?

A) Many monocots have a distinct palisade layer.
B) Many monocots lack a petiole.
C) Many monocots lack a distinct spongy layer.
D) Many monocot leaves are narrow.
E) Many monocot leaves wrap around the stem forming a sheath.

Question 38

Transpiration:

A) declines in areas where forests have been cleared.
B) is a relatively minor component of the global hydrological cycle.
C) is a synonym for precipitation.
D) is significant to climate issues, but only in relationship to tropical rainforests.
E) does not occur in India due to the local geographic conditions and extent of ocean surface.

Question 39

The needles of pines and other conifers are adapted to:

A) conserve water.
B) defend against herbivores.
C) reduce the effects of intense sunlight.
D) reduce the effects of snow and ice.
E) reduce the effects of wind.

Question 40

In the mechanism of stomatal opening, after light activates proton pumps which of the following happens next?

A) Guard cells change shape.
B) Hydrogen ions are actively transported out of guard cells.
C) Potassium ions diffuse into guard cells.
D) Chloride ions diffuse out of guard cells.
E) Water moves by osmosis into guard cells.

Question 41

The bundle sheath typically surrounds the larger veins.
____________________

Question 42

Modified leaves that protect meristematic tissue at the tips of woody plants are known as:

A) bulbs.
B) bud scales.
C) spines.
D) tendrils.
E) scale scars.

Question 43

Compare the leaf structure of monocots and eudicots.

Question 44

Subsidiary cells are the only epidermal cells that have chloroplasts.
____________________

Question 45

A cross section of a monocot leaf typically shows veins in both cross-section and lengthwise section.
____________________

Question 46

Identify and describe:
A.
three different ways in which leaves can be arranged on stems, and list one example for each.
B.
three different venation patterns in leaves and whether each is characteristic of eudicots or monocots.

Question 47

Underground stems with fleshy leaves used for storage of water and food are known as:

A) tendrils.
B) spines.
C) bulbs.
D) buds.
E) stipules.

Question 48

Leaf abscission is initiated and orchestrated by changing levels of the plant hormone __________.

A) ethylene
B) cytokinin
C) auxin
D) abscisic acid
E) gibberellin

Question 49

An alternate leaf arrangement is one in which there is one leaf per node.
____________________

Question 50

In cactus plants, the__________ is the main organ of photosynthesis.

A) leaf
B) spine
C) stem
D) flower
E) fruit

Question 51

Palisade mesophyll is a tissue typically found on the side of the leaf toward the upper epidermis.

Question 52

Parallel venation is characteristic of eudicot leaves.
____________________

Question 53

The spines of a cactus are actually modified:

A) branches.
B) stems.
C) leaves.
D) roots.
E) trichomes.

Question 54

Insectivorous plants:

A) typically grow in nutrient-rich soil.
B) enhance a poor supply of CO₂ through capturing prey.
C) use modified leaves to trap their prey.
D) require symbiotic insects and insect larvae to digest their prey.
E) require microorganisms to digest their prey.

Question 55

Leaf abscission:

A) occurs as a response to increased temperatures.
B) occurs as a response to dry conditions.
C) involves the formation of a tendril at the base of the petiole.
D) occurs year-round on deciduous plants.
E) does not occur in conifers.

Question 56

Identify three different types of modified leaves and list the function of each.

Question 57

The release of liquid water by leaves when soil moisture is high is known as:

A) vaporization.
B) photosynthesis.
C) guttation.
D) transpiration.
E) abscission.

Question 58

A leaf without a blade is said to be sessile.
____________________

Question 59

Which of the following is not associated with leaf abscission?

A) Chlorophyll breaks down.
B) Anthocyanins accumulate.
C) A layer of cork develops.
D) The middle lamella is strengthened.
E) Carotenoids become visible.

Question 60

The area where the petiole detaches from the stem is referred to as the:

A) abscission zone.
B) middle lamella.
C) bundle sheath extension.
D) terminal bud.
E) bud scale scar.

Question 61

MATCHING
Indicate whether each of the following characteristics is generally found in monocots or in eudicots.
a.monocots
b.eudicots
exhibit pinnately netted venation

Question 62

MATCHING
Indicate whether each of the following characteristics is generally found in monocots or in eudicots.
a.monocots
b.eudicots
Explain how the movement of hydrogen and potassium ions across the membranes of guard cells opens and closes the stomata.

Question 63

A spine is a modified branch.
____________________

Question 64

MATCHING
Indicate whether each of the following characteristics is generally found in monocots or in eudicots.
a.monocots
b.eudicots
mesophyll usually differentiated into palisade and spongy layers

Question 65

Describe the benefits of transpiration to plants.

Question 66

MATCHING
Indicate whether each of the following characteristics is generally found in monocots or in eudicots.
a.monocots
b.eudicots
guard cells may be dumbbell shaped

Question 67

MATCHING
Indicate whether each of the following characteristics is generally found in monocots or in eudicots.
a.monocots
b.eudicots
exhibit parallel venation

Question 68

Stomata close as a result of water moving into guard cells.
____________________

Question 69

Most transpiration occurs through stomata.
____________________

Question 70

MATCHING
Indicate whether each of the following characteristics is generally found in monocots or in eudicots.
a.monocots
b.eudicots
have a petiole

Question 71

MATCHING
Indicate whether each of the following characteristics is generally found in monocots or in eudicots.
a.monocots
b.eudicots
leaf forms a sheath at the leaf base

Question 72

Leaf abscission is initiated and orchestrated by the hormone abscisic acid.
____________________

Question 73

Red light has a wavelength that is the most effective for triggering stomatal opening.
____________________

Question 74

MATCHING
Indicate whether each of the following characteristics is generally found in monocots or in eudicots.
a.monocots
b.eudicots
Explain how the structure of a leaf contributes to the function of photosynthesis.

Question 75

MATCHING
Indicate whether each of the following characteristics is generally found in monocots or in eudicots.
a.monocots
b.eudicots
exhibit palmately netted venation

Question 76

Guttation is the process most responsible for moving water and minerals through the plant.
____________________