Deck 35: Stem Structure and Transport

Question 1

Which of the following is a function of stems?

A) sexually reproduce
B) absorb nutrient minerals
C) produce new tissues
D) transport dissolved gases
E) anchor plants

Answer 1

C

Question 2

Unlike herbaceous eudicot stems, monocot stems do not have distinct areas of cortex and pith. Instead, their ____ functions as the cortex and pith.

A) endodermis
B) ground tissue
C) meristem
D) vascular cambium
E) periderm

Answer 2

B

Question 3

____ join roots to leaves and may be above or underground.

A) Vines
B) Stems
C) Petioles
D) Flowers
E) Runners

Answer 3

B

Question 4

Figure 35-1 In the accompanying figure, the function of the structure labeled as 1 represents:

A) the formation of pith.
B) protection.
C) conduction of water and dissolved minerals from the roots.
D) conduction of sugars from the leaves.
E) photosynthesis.

Question 5

Figure 35-1 In the accompanying figure, the structure labeled as 3 is:

A) the secondary xylem.
B) formed by the division of the vascular cambium.
C) found adjacent to the pith.
D) usually referred to as wood.
E) the cork cambium.

Question 6

Which of the following statements about the cortex is true?

A) It secretes a protective layer of cutin.
B) It is at the core of the herbaceous eudicot stem.
C) It is filled with cork cells.
D) It translocates sugar by means of a pressure gradient.
E) It may contain collenchyma and sclerenchyma.

Question 7

Dissolved sugars are transported in:

A) cork cambium.
B) epidermis.
C) pith.
D) phloem.
E) xylem.

Question 8

Secondary growth occurs as a result of the activity of which two lateral meristems?

A) vascular cambium and cork cambium
B) apical meristem and cork cambium
C) primary meristem and secondary meristem
D) periderm and cork cambium
E) apical meristem and vascular cambium

Question 9

____ is the functional replacement for the epidermis.

A) Xylem
B) Periderm
C) Pith
D) Cortex
E) Cork

Question 10

Monocots such as palms and bamboo achieve considerable increase in girth by:

A) a modified form of secondary growth in which parenchyma cells divide and enlarge.
B) primary growth.
C) a modified form of primary growth in which parenchyma cells divide and enlarge.
D) enlargement of primary xylem.
E) enlargement of primary phloem.

Question 11

Which of the following statements about monocots is true?

A) They lack sclerenchyma tissue.
B) They have a well-developed vascular cambium.
C) They do not produce bark.
D) Their lateral meristems give rise to wood.
E) Secondary growth occurs rather slowly.

Question 12

One function of cortical parenchyma cells is:

A) photosynthesis.
B) to provide structural support and strength.
C) to produce cutin.
D) to conduct water and nutrient minerals.
E) to conduct sugars.

Question 13

At the center of an herbaceous eudicot stem is:

A) pith.
B) collenchyma.
C) sclerenchyma.
D) vascular cambium.
E) phloem.

Question 14

Periderm is produced by:

A) xylem.
B) cork cambium.
C) pith.
D) cortex.
E) phloem.

Question 15

Vascular cambium gives rise to which of the following tissues?

A) primary phloem
B) periderm
C) epidermis
D) secondary xylem
E) cork cambium

Question 16

Cork cambium and the tissues it produces are collectively known as:

A) periderm.
B) epidermis.
C) xylem.
D) pith.
E) cortex.

Question 17

Cells produced on the inside of the vascular cambium differentiate to form which vascular tissue?

A) cork cambium
B) primary phloem
C) primary xylem
D) secondary phloem
E) secondary xylem

Question 18

Figure 35-1 In the accompanying figure, the structure labeled as 2 is:

A) known as wood.
B) produced by cork cambium (not shown).
C) composed largely of secondary tissue.
D) composed largely of cells that are alive at maturity.
E) commonly called scales.

Question 19

The outermost cell layer of herbaceous stems is the:

A) bark.
B) cortex.
C) endodermis.
D) epidermis.
E) periderm.

Question 20

The thin layer of meristematic cells located between xylem and phloem is referred to as the:

A) apical meristem.
B) collenchyma.
C) cork cambium.
D) vascular cambium.
E) pith.

Question 21

Which of the following statements about heartwood is false ?

A) It functions in conduction.
B) It is a storage site for waste products.
C) It is resistant to decay.
D) It provides structural support.
E) It is located in the center of a tree.

Question 22

Figure 35-2 In the accompanying figure, the structure responsible for photosynthesis, storage, and support is labeled as:

A) 1
B) 2
C) 3
D) 4
E) 5

Question 23

Figure 35-3 In the accompanying figure, the structure labeled as ____ is formed in the leaf scars by vascular tissue that extends from the stem out into the leaf.

A) 5
B) 6
C) 7
D) 8
E) 9

Question 24

In woody plants, the lateral transport of materials occurs through:

A) lenticels.
B) pith.
C) pith rays.
D) phloem fiber caps.
E) rays.

Question 25

Functional secondary xylem that conducts water and dissolved minerals is known as:

A) softwood.
B) springwood.
C) hardwood.
D) sapwood.
E) heartwood.

Question 26

____ is denser than ____.

A) Heartwood; sapwood
B) Heartwood; softwood
C) Sapwood; hardwood
D) Sapwood; heartwood
E) Softwood; hardwood

Question 27

Figure 35-2 In the accompanying figure, the cell layer that contains xylem is labeled as:

A) 1
B) 2
C) 3
D) 4
E) 5

Question 28

Softwood is the wood:

A) found at the center of a tree.
B) of cone-bearing gymnosperms.
C) of flowering plants.
D) formed when water is abundant.
E) formed when water is less abundant.

Question 29

Secondary xylem contains all of the following cell types except :

A) tracheids.
B) vessel elements.
C) sieve tube elements
D) fibers.
E) parenchyma.

Question 30

Figure 35-3 What is the age of the twig in the accompanying figure?

A) 0 years
B) 1 year
C) 2 years
D) 3 years
E) 5 years

Question 31

____ is the wood of flowering plants and ____ is the wood of conifers.

A) Hardwood; softwood
B) Summer wood; spring wood
C) Softwood; hardwood
D) Spring wood; summer wood
E) Heartwood; softwood

Question 32

Concentric rings found in the cross section of the wood of trees are known as:

A) summer rings.
B) spring rings.
C) annual rings.
D) dendrochrons.
E) pith rings.

Question 33

Although the same cell types can be found in both primary and secondary phloem, ____ are usually more abundant in secondary phloem.

A) parenchyma
B) fibers
C) vessel elements
D) companion cells
E) sieve tube members

Question 34

____ is when liquid water is forced out of the surface of leaves.

A) Root pressure
B) Transpiration
C) Guttation
D) Hydration
E) Translocation

Question 35

Embryonic shoots located at the tips of stems are called ____, while those located in the axils are known as ____.

A) nodes; internodes
B) axillary buds; terminal buds
C) terminal buds; axillary buds
D) axillary buds; lateral buds
E) bud scales; bud scale scars

Question 36

Dendrochronology can be useful in determining:

A) the dates of past earthquakes and volcanic eruptions.
B) future climate patterns.
C) the solution to global warming.
D) how tree growth affects air pollution.
E) the time of day.

Question 37

Lenticels function to:

A) protect undeveloped embryonic shoots.
B) permit gas exchange through the periderm.
C) support leaves and flowers.
D) absorb water and dissolved nutrient minerals.
E) anchor a plant in the ground.

Question 38

Water moves from a region of ____ water potential to a region of ____water potential.

A) more positive; less positive
B) less positive; more positive
C) less negative; more negative
D) more negative; less negative
E) more negative; zero

Question 39

Water and dissolved mineral are transported laterally from the secondary ____ to the secondary ____.

A) phloem; xylem
B) epidermis; peridem
C) vascular cambium; cork cambium
D) periderm; epidermis
E) xylem; phloem

Question 40

Sapwood develops from:

A) secondary xylem
B) secondary phloem
C) primary phloem
D) primary xylem
E) cork parenchyma

Question 41

The loading of dissolved sugars into the sieve tube elements of phloem is:

A) passive transport.
B) active transport.
C) osmosis.
D) simple diffusion.
E) facilitated diffusion.

Question 42

Identify four external features of a woody twig and briefly explain the function and/or origin of each.

Question 43

According to the pressure-flow model, ____.

A) water moves from an area of positive water potential to an area of negative water potential
B) the evaporative pull of transpiration produces tension at the top of the plant
C) the flow of sugar is driven by a pressure gradient between the source and the sink
D) pressure is created by the movement of water into the roots from the soil
E) the production of sugar pushes it out of the chloroplast and into the xylem

Question 44

Using severed aphid mouthparts, scientists have verified that in most species the phloem translocates mostly ____, but that ____ may also be translocated.

A) glucose; amino acids
B) glucose; sugar alcohols
C) glucose; cellulose and starch
D) sucrose; raffinose and sorbitol
E) sucrose; glucose

Question 45

Guttation results from:

A) water pressure.
B) transpiration pull.
C) osmotic pressure.
D) root pressure.
E) sink-to-source transport.

Question 46

Periderm is the functional replacement of the bark .

Question 47

Water is capable of rising to the tops of the tallest trees due to the:

A) chemical bonds of water molecules.
B) push of gravity.
C) adhesion of water molecules to each other.
D) push of ground water.
E) pull of transpiration.

Question 48

When cells of the vascular cambium divide, they produce xylem toward the outside.

Question 49

Xylem transports water and dissolved nutrient minerals in which direction?

A) upward
B) downward
C) inward laterally
D) outward laterally
E) both upward and downward

Question 50

Sugar is translocated in phloem from a source, or an area of ____, to a sink, or an area of ____.

A) low sugar concentration; high sugar concentration
B) high sugar concentration; low sugar concentration
C) positive water potential; negative water potential
D) negative water potential; positive water potential
E) low pressure; equally low pressure

Question 51

____ is the predominant photosynthetic product carried in phloem.

A) Glucose
B) Cellulose
C) Sucrose
D) Maltose
E) Fructose

Question 52

In a(n) monocot stem, vascular bundles are arranged in a circle.

Question 53

Bundle scars would be found within a(n) leaf scar .

Question 54

In the very center of a(n) monocot stem is pith.

Question 55

Immediately inside the epidermis of a eudicot stem is the pith .

Question 56

Compare and contrast the structure of an herbaceous eudicot stem and that of a monocot.

Question 57

Diagram and label a cross section of 1) a woody stem before the vascular cambium becomes active and 2) a woody stem from the same plant after the vascular cambium has been active for a considerable length of time.

Question 58

Sapwood is functional secondary xylem.

Question 59

Before being loaded into the phloem for translocation, the carbohydrates produced during photosynthesis must be converted into which molecule?

A) glucose
B) fructose
C) maltose
D) sucrose
E) galactose

Question 60

Compare transpiration and translocation, and be sure to cover the five points below.
1. Principle substance(s) transported
2. Direction of transport
3. Tissue through which transport occurs
4. Name of model that explains the process
5. Does the plant expend energy to carry out the process?

Question 61

How is it possible for water to defy gravity and travel from the roots to the tops of plants? Use the tension-cohesion model to explain your answer.

Question 63

The transport of xylem sap is the most rapid movement of any material in plants.

Question 65

Water is transported vertically through the plant via the process of translocation .

Question 67

In a plant, most water is transported vertically by being pushed to the top.

Question 68

If you were to take a cross section of a tree from the tropics, would you be able to determine the accurate age of the tree? Why or why not?

Question 69

Springwood has narrower conducting cells and many fibers.

Question 70

Sucrose is translocated from source to sink .

Question 71

Hardwood is the wood of gymnosperms .

Question 72

Explain how dissolved sugar is transported in the phloem by means of a pressure gradient.

Question 73

A growth ring is composed of xylem .

Question 74

Sugars are loaded into sieve tubes via simple diffusion .

Question 75

One reason that water is able to form unbroken columns is because water molecules are cohesive .