Chapter 36: Transport in Vascular Plants
Chapter Quiz

Chapter Quiz

1 .       The proton pump _____. (Concept 36.1E-Book) [Hint]

 pumps H+ out of the cell
 pumps H+ into the cell
 generates energy by producing ATP
 provides energy for active transport
 none of the above

2 .       Which of the following processes is aided by the membrane potential established by the proton pump? (Concept 36.1E-Book) [Hint]

 uptake of cations such as K+
 cotransport of anions
 cotransport of neutral solutes
 The second and third answers are correct.
 All of the above answers are correct.

3 .       A plant cell placed in a solution with a higher water potential will _____. (Concept 36.1E-Book) [Hint]

 lose water and crenate
 lose water and become turgid
 gain water and become turgid
 lose water and plasmolyze
 gain water and plasmolyze

4 .       A cell has a pressure potential of 0 and a solute potential of -0.7 MPa. What is its water potential? (Concept 36.1E-Book) [Hint]

 -0.7 MPa
 0 MPa
 0.7 MPa
 > -0.7 MPa
 < -0.7 MPa

5 .       If pure water is separated from a 0.1 M solution in a U-shaped tube by a membrane impermeable to the solute, what will happen? (Concept 36.1E-Book) [Hint]

 Water will move to the 0.1 M solution side until the concentrations are equal on both sides of the membrane.
 Solute in the solution will diffuse to the pure water side until equilibrium is reached.
 Water will diffuse toward the solution side until a piston pushes it back at an equal rate.
 Water will diffuse to the solution side until the pressure potential due to a higher water column is equal, but opposite in sign, to the osmotic potential.
 All the water will diffuse to the solution side.

6 .       Which of the following is true for a plant that is wilting? (Concept 36.1E-Book) [Hint]

 The pressure potential in the xylem will be more negative than in a turgid plant.
 The pressure potential in guard cells will be high to keep them closed.
 The pressure potential in endodermal cells will be positive.
 Root hair cells will have a positive pressure potential.
 Mesophyll cells will have a positive pressure potential.

7 .       In a turgid cell _____. (Concept 36.1E-Book) [Hint]

 Ψs is always positive
 Ψp is 0
 Ψ = 0
 Ψp ≤ 0
 Ψ = Ψs

8 .       Water molecules cross a plasma membrane of a plant cell due to _____. (Concept 36.1E-Book) [Hint]

 transport proteins
 changes in the second messengers such as Ca+2
 all of the above

9 .       The cytoplasmic continuum connecting neighboring cells is called the _____. (Concept 36.1E-Book) [Hint]

 cell wall

10 .       The continuum of cell walls connecting neighboring cells is defined as the _____. (Concept 36.1E-Book) [Hint]


11 .       Which of the cells below are involved with bulk flow? (Concept 36.2E-Book) [Hint]

 tracheids, vessels, and sieve tubes
 tracheids, vessels, and guard cells
 tracheids, tonoplasts, and sieve tubes
 guard cells, vessels, and sieve tubes
 tracheids, vessels, and tonoplasts

12 .       The most direct route for water from the soil to the xylem is via the _____. (Concept 36.2E-Book) [Hint]

 cells of the cortex
 Casparian strip

13 .       The greatest increase in surface area for absorption in the root is due to _____. (Concept 36.1E-Book) [Hint]

 branch roots
 root hairs
 root nodules
 formation of a periderm

14 .       A botanist discovered a mutant plant that is unable to produce the material that forms the Casparian strip. This plant is _____. (Concept 36.2E-Book) [Hint]

 unable to fix nitrogen
 unable to transport water or solutes to the leaves
 able to exert greater root pressure than normal plants
 unable to control the amounts of water and solutes it absorbs
 unable to lose water by transpiration

15 .       In a plant root, the one cell type in which water cannot move via the apoplast is the _____. (Concept 36.2E-Book) [Hint]

 vascular tissues

16 .       A friend of yours has a terrarium on her windowsill containing various houseplants. She wonders why the glass is often fogged with water droplets. What would you tell her is the cause of the droplets? (Concept 36.3E-Book) [Hint]

 root pressure
 pressure flow

17 .       Root pressure is attributable to _____. (Concept 36.3E-Book) [Hint]

 accumulation of minerals in the vascular cylinder
 the high water potential of the vascular cylinder relative to the root cortex
 the pumping of minerals out of the vascular cylinder

18 .       Which of the following conditions will result in the fastest transport through the xylem in a tree, assuming adequate water supply in the roots? (Concept 36.1E-Book and Concept 36.3E-Book) [Hint]

 negative pressure potential in the leaf mesophyll
 positive pressure potential in the xylem
 positive pressure potential in the mesophyll
 negative pressure potential in the guard cells
 phloem transport being in the opposite direction from the xylem transport

19 .       What keeps the force of gravity from overcoming transpirational pull? (Concept 36.3E-Book) [Hint]

 upward pressure from the roots
 high water pressure in the leaves
 the Casparian strip blocking water molecules from moving out
 movement of water toward a sugar sink
 cohesion and adhesion of water molecules

20 .       Normally when an aphid feeds by puncturing plant tissues, it does not have to suck the sap out. If an aphid, however, inserted its feeding tube in the wrong place, the fluid in the aphid's guts could be sucked out through the feeding tube. What could explain this phenomenon? (Concept 36.3E-Book) [Hint]

 The aphid pierced the Casparian strip.
 The aphid punctured a root nodule.
 The aphid punctured xylem cells.
 The aphid punctured a sieve tube cell.
 The aphid punctured a stoma.

21 .       During winter, tree sap can sometimes freeze and cavitation (the formation of an air pocket) may occur. Which one of the following mechanisms of sap transport would you expect to be most immediately affected by cavitation? (Concept 36.3E-Book) [Hint]

 symplast function
 pressure flow (mass flow)
 cohesion transpiration
 root pressure
 active transport

22 .       What is the main source of energy that moves water upward in the trunk of a tree? (Concept 36.2E-Book) [Hint]

 contraction of xylem cells
 evaporation of water by the sun
 pressure exerted by root cells
 breakdown and release of energy of sugar molecules
 osmotic changes caused by alterations in salt content

23 .       The rate of transpiration is expected to be greatest on a _____ day. (Concept 36.2E-Book) [Hint]

 cool and moist
 warm and moist
 cool and dry
 warm and dry
 windy and cool

24 .       What contributes directly to the turgor pressure that opens and closes stomata? (Concept 36.4E-Book) [Hint]

 potassium accumulation in guard cells

25 .       Stomata open during the day in response to _____. (Concept 36.4E-Book) [Hint]

 blue light triggering the efflux of K+ from guard cells
 increased temperatures
 increased CO2 levels
 blue light triggering the uptake of K+ by guard cells
 the production of abscisic acid

26 .       Which of the following describes how some plants are adapted to arid environments? (Concept 36.4E-Book) [Hint]

 They can fix carbon from carbon dioxide even when stomata are closed.
 They lose more water to transpiration than C3 plants.
 They have evolved alternatives to the Calvin cycle.
 They can leave their stomata open even on very hot, dry days.
 All of the above.

27 .       In an apple tree that is producing sugars, sugar might flow from _____ to _____. (Concept 36.5E-Book) [Hint]

 a developing apple ... a mature leaf
 the trunk ... a leaf
 a growing root ... a growing shoot tip
 a leaf ... a developing apple
 a growing shoot tip ... the trunk

28 .       Companion cells that are specialized for the transport of sugar between apoplast and symplast are _____ cells. (Concept 36.5E-Book) [Hint]


29 .       Which aspect of solute transport in the xylem of a plant is most like that of solute transport in the phloem? (Concept 36.3E-Book and Concept 36.5E-Book) [Hint]

 the upward movement from roots to leaves
 the development of root pressure
 movement in conduits composed of nonliving cell walls
 the development of tension on water to pull it and dissolved solutes through the conduits
 the dependence of the process on transpiration from the leaves

30 .       When referring to phloem transport, the "sink" in roots is created by _____. (Concept 36.5E-Book) [Hint]

 the active transport of mineral ions into xylem cells
 the osmosis of water into xylem cells
 the absorption of water from the soil through epidermal cells
 the active transport of sugars from phloem to cortex cells
 all of the above

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