Lesson 4: Structure, Growth, Development and Transport in Plants

Question 1

Which of the following statements is false about bulk flow?

A. It depends on a difference in pressure potential at
the source and sink.
B. It is driven primarily by pressure potential.
C. It depends on the force of gravity on a column of
water.
D. It may be the result of either positive or negative
pressure potential.
E. It is more effective than diffusion over distances
greater than 100 μm.

Answer 1

C. It depends on the force of gravity on a column of water.

Question 2

What tissue makes up most of the wood of a tree?

A. primary xylem
B. secondary xylem
C. vascular cambium
D. mesophyll cells
E. secondary phloem

Answer 2

B. secondary xylem

Question 3

Which of the following have unevenly thickened primary walls that support young, growing parts of the plant?

A. tracheids and vessel elements
B. sieve-tube elements
C. collenchyma cells
D. parenchyma cells
E.sclerenchyma cells

Answer 3

C. collenchyma cells

Question 4

Which one of the following statements about the transport of nutrients in phloem is false?

A. A sink may be located anywhere in the plant.
B. A sink is that part of the plant where a particular
solute is consumed or stored.
C. Companion cells control the rate and direction of
movement of phloem sap.
D. Solute particles can be actively transported into
phloem at the source.
E. Differences in osmotic concentration at the source
and sink cause a hydrostatic pressure gradient to be
formed.

Answer 4

C. Companion cells control the rate and direction of movement of phloem sap.

Question 5

Which of the following root tissues gives rise to lateral roots?

A. epidermis
B. pericycle
C. endodermis
D. phloem
E. cortex

Answer 5

B. pericycle

Question 6

A water molecule could move all the way through a plant from soil to root to leaf to air and pass through a living cell only once. This living cell would be a part of which structure?

A. the root epidermis
B. the root cortex
C. a guard cell
D. the endodermis
E. the Casparian strip

Answer 6

D. the endodermis

Question 7

The vascular bundle in the shape of a single central cylinder in a root is called the

A. periderm.
B. cortex.
C. stele.
D. pith.
E. endodermis.

Answer 7

C. stele.

Question 8

Guard cells do which of the following?

A. guard against mineral loss through the stomata
B. accumulate K+ and close the stomata
C. help balance the photosynthesis-transpiration
compromise
D. contain chloroplasts that import K+ directly into the
cells
E. protect the endodermis

Answer 8

C. help balance the photosynthesis-transpiration compromise

Question 9

Which of the following is a true statement about growth in plants?

A. Some plants lack secondary growth.
B. Only primary growth is localized at meristems.
C. Only secondary growth produces reproductive
structures.
D. Monocots have only primary growth, and eudicots
have only secondary growth.
E. Only stems have secondary growth.

Answer 9

A. Some plants lack secondary growth.

Question 10

Phloem transport is described as being from source to sink. Which of the following would most accurately complete this statement about phloem transport as applied to most plants in the late spring?
Phloem transports ________ from the ________ source to the ________ sink.

A. sugars; leaf; apical meristem
B. nucleic acids; flower; root
C. sugars; stem; root
D. amino acids; root; mycorrhizae
E. proteins; root; leaf

Answer 10

A. sugars; leaf; apical meristem

Question 11

Which cells in a root form a protective barrier to the vascular system where all materials must move through the symplast?

A. epidermis
B. exodermis
C. cortex
D. pericycle
E. endodermis

Answer 11

E. endodermis

Question 12

Choose the option that best describes the relationship between the cell wall thickness of parenchyma cells versus sclerenchyma cells.

A. The cell walls of both types of cells are roughly
equal.
B. The cell walls of parenchyma cells are thinner than
those of sclerenchyma cells.
C. The cell walls of parenchyma cells are thicker than
those of sclerenchyma cells.
D. The thickness of the cell walls for both types of cells
is too variable for a comparison to be made.

Answer 12

B. The cell walls of parenchyma cells are thinner than those of sclerenchyma cells.

Question 13

The opening of stomata is thought to involve

A. decreased turgor pressure in guard cells.
B. movement of K+ from the guard cells.
C. an increase in the solute concentration of the guard
cells.
D. active transport of water out of the guard cells.
E. a decrease in the solute concentration of the stoma.

Answer 13

C. an increase in the solute concentration of the guard cells.

Question 14

An open beaker of pure water has a water potential (Ψ) of
[Ψ ψ]

A. -0.0000001 MPa.
B. 0.0 (zero).
C. -0.23 MPa.
D. +0.07 MPa.
E. +0.23 MPa.

Answer 14

B. 0.0 (zero).

Question 15

Axillary buds

A. have dormant meristematic cells.
B. do not form a vascular connection with the primary
shoot.
C. grow immediately into shoot branches.
D. are initiated by the cork cambium.
E. is composed of a series of internodes lacking nodes.

Answer 15

A. have dormant meristematic cells.

Question 16

Which structure is incorrectly paired with its tissue system?

A. guard cell—dermal tissue
B. tracheid—vascular tissue
C. palisade parenchyma—ground tissue
D. companion cell—ground tissue
E. root hair—dermal tissue

Answer 16

D. companion cell—ground tissue

Question 17

All of the following normally enter the plant through the roots except

A. water.
B. potassium.
C. carbon dioxide.
D. calcium.
E. nitrogen.

Answer 17

C. carbon dioxide.

Question 18

Water potential is generally most negative in which of the following parts of a plant?

A. xylem vessels in leaves
B. root hairs
C. mesophyll cells of the leaf
D. xylem vessels in roots
E. cells of the root cortex

Answer 18

C. mesophyll cells of the leaf

Question 19

Hypothetically, one of the major benefits of double fertilization in angiosperms is to

A. coordinate developmental timing between the
embryo and its food stores.
B. promote diversity in flower shape and colour.
C. emphasize embryonic survival by increasing embryo
size.
D. decrease the potential for mutation by insulating the
embryo with other cells.
E. increase the number of fertilization events and
offspring produced.

Answer 19

A. coordinate developmental timing between the embryo and its food stores.

Question 20

Which of the following was not a challenge for the survival of the first land plants?

A. sources of water
B. absorbing enough light
C. sperm transfer
D. desiccation
E. animal predation

Answer 20

E. animal predation

Question 21

All of the following have an effect on water potential (Ψ) in plants except

A. osmosis.
B. water-attracting matrices.
C. dissolved solutes.
D. physical pressure.
E. DNA structure.

Answer 21

E. DNA structure.