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

Dissolved sugars are transported in:

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

Answer 2

D

Question 3

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.

Answer 3

C

Question 4

Monocot stems do not possess __________ that gives rise to secondary growth.

A) sclerenchyma tissue
B) lateral meristems
C) parenchyma tissue
D) apical meristems
E) vascular tissue

Question 5

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 6

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 7

Periderm arises from ________.

A) xylem
B) cork cambium
C) pith
D) cortex
E) sclerenchyma

Question 8

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 9

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 10

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 11

Vascular cambium gives rise to which of the following tissues?

A) Primary phloem
B) Periderm
C) Epidermis
D) Secondary xylem
E) Cork cambium

Question 12

Periderm is produced by:

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

Question 13

The outermost cell layer of herbaceous stems is the:

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

Question 14

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 15

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 16

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 17

Vascular bundles of herbaceous _______ stems are arranged in a circle in cross section.

A) prodicot
B) monocot
C) eudicot
D) bryophyte
E) halophyte

Question 18

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 19

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

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

Question 20

At the center of an herbaceous eudicot stem is:

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

Question 21

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 22

____ is when water vapor evaporates from leaves.

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

Question 23

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 24

The arrangement of the different cell types in secondary ______ produces the distinctive wood characteristics of each species.

A) parenchyma
B) xylem
C) phloem
D) cambium
E) ground tissue

Question 25

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 26

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

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

Question 27

____ is less dense than ____.

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

Question 28

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 29

Figure 35-3 ​

In the accompanying figure, the structure labeled as ____ will form branches.

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

Question 30

Water and dissolved mineral are transported laterally through chains of ____.

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

Question 31

Embryonic shoots located at the tips of stems are covered by ____.

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

Question 32

Hardwood is the wood of _____ and softwood is the wood of ____.

A) flowering plants; conifers
B) conifers; flowering plants
C) conifers; bryophytes
D) flowering plants; bryophytes
E) conifers; ferns

Question 33

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 34

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 35

Secondary xylem contains all of the following cell types except :

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

Question 36

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 37

Sapwood develops from:

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

Question 38

The driving force for the movement of water in plants is difference in water _______.

A) pressure
B) osmolarity
C) potential
D) temperature
E) pH

Question 39

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

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

Question 40

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 41

Periderm is the functional replacement of the bark.

Question 42

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 43

The transport of sucrose from companion cells into sieve tube elements depends upon ______.

A) diffusion
B) pump
C) cotransport
D) antitransport
E) osmosis

Question 44

Compare transpiration and translocation, and be sure to cover the five points below.
1. Principal 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 45

Using severed aphid mouthparts, scientists have verified that, in most species, the phloem can translocate ____, _____, and _______.

A) glucose; xylitol; amino acids
B) sucrose; cholesterol, glycerol
C) glucose; ribose, starch
D) sucrose; raffinose, sorbitol
E) sucrose; glucose; fructose

Question 46

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 47

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 48

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

Question 49

The predominant photosynthetic product carried in phloem is _______.

A) glucose
B) water
C) sucrose
D) oxygen
E) carbon dioxide

Question 50

Sugar is translocated in phloem from a ______, an area of high sugar concentration, to a ______, an area of low sugar concentration.

A) root; leaf
B) source; sink
C) sink; root
D) leaf; source
E) sink; source

Question 51

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 52

Bundle scars would be found within a leaf scar.

Question 53

Guttation results from:

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

Question 54

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

Question 55

Sapwood is functional secondary xylem.

Question 56

In the very center of a monocot stem is pith.

Question 57

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

Question 58

Define water potential and explain how it affects water flow.

Question 59

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

Question 60

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 64

A growth ring is composed of xylem.

Question 65

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 66

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

Question 68

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

Question 69

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

Question 70

Springwood has narrower conducting cells and many fibers.

Question 71

Sugars are loaded into sieve tubes via simple diffusion.

Question 76

Hardwood is the wood of gymnosperms.

Question 77

Describe how water potential is related to water movement in a plant.

Question 78

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

Question 79

Sucrose is translocated from source to sink.

Question 80

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