Transport in Plants-Chapter 37

Question 1

____________ is used to predict which way water will move. measure in MPa or _____________.

Answer 1

water potential

megapascals

Question 2

water always moves from _______ to _________ water potential

Answer 2

high to low

Question 3

the total potential energy of water in the cell is the __________

Answer 3

water potential

Question 4

water moves in the direction that eventually results in ____________

Answer 4

equilibrium

Question 5

water will move towards the greater amount of solute in efforts to dilute the sample

Answer 5

true

Question 6

when water moves into a cell, it becomes swollen or _________. when water moves out of the cell, it will shrink and become __________ (___________ occurs)

Answer 6

turgid
plasmolysis
flaccid

Question 7

water channels that exist in vacuole and cell membranes, speed up osmosis, allow for equilibrium to be established quickly

Answer 7

aquaporins

Question 8

long distance movement of water is assisted by a pulling force called _____________

Answer 8

transpiration

Question 9

was you move up a a plant from the roots, the water potential ____________ which allows water to move against gravity and up the plant

Answer 9

decreases

Question 10

water moves……….

Answer 10

into the roots, up the xylem, fills the empty spaces in between the mesophyll cells in the leaf, and evaporates through the stoma

Question 11

water moves into the roots only if the soil’s water potential is ____________. usually happens because the water is freshwater, root has more solutes than freshwater. roots are usually turgid

Answer 11

greater

Question 12

absorb most of the plant’s water, collectively provide enormous surface areas

Answer 12

root hairs

Question 13

surface area for water and mineral absorption is further increased by ______________ fungi, particularly helpful in phosphorous uptake

Answer 13

mycorhizae

Question 14

water and minerals cannot travel between cells, they must travel through the cell via the symplastic route, plants can regulate fluid and ion concentration before entering the xylem, watertight later in between endodermis cells

Answer 14

casparian strip

Question 15

channels of dead cells that function as vascular tubes, the water moves from the root hairs and ground tissue, lower water potential than the roots, runs the length of the plants and ends in the leaves

Answer 15

xylem

Question 16

Why doesn’t water move down the xylem?

Answer 16

(1) tensile strength
(2) water coheres to itself
(3) water adheres to the the walls due to its polarity

Question 17

tensile strength varies ___________ with diameter

Answer 17

inversely

Question 18

a _________ can break tensile strength, causes an expansion of blockage within the vessel, known as an embolism or cavitation

Answer 18

air bubble

Question 19

__________ have lower water potential than xylem, filled with air between mesophyll, water evaporates into the air in these spaces

Answer 19

leaves

Question 20

water vapor leaves the leaf through the ______

Answer 20

stoma

Question 21

the outside air has a _______________ compared to the leaf

Answer 21

lower water potential

Question 22

rate of transpiration is managed by __________

Answer 22

guard cells

Question 23

closing the __________ can control water loss on a short-term basis, must be open at some point to allow CO2 entry

Answer 23

stomata

Question 24

When do the stomata close?

Answer 24

during high temperatures and when CO2 concentrations increase

Question 25

When do the stomata open?

Answer 25

when blue wavelengths of light promote uptake K+ by the guard cells

Question 26

Do alternative photosynthetic pathways reduce or increase transpiration rates?

Answer 26

reduce

Question 27

guard cells have thicker cell walls on the __________, the are open because they bulge and blow outward when turgid

Answer 27

inside

Question 28

What 3 substances are absorbed by guard cells?

Answer 28

potassium, chloride, and malate

Question 29

what is the substance that initiates a signaling pathway to close the stomata in drought stress

Answer 29

abscisic acid (ABA), ion channels open and water leaves guard cells to retain water in structure

Question 30

ions move into the roots at night when no transpiration is occurring, lowers water potential in roots

Answer 30

root pressure

Question 31

if enough root pressure occurs, ___________ is seen on leaf surfaces

Answer 31

guttation (dew)

Question 32

What are the 3 transport routes within a cell?

Answer 32

(1) apoplast route
(2) symplast route
(3) transmembrane route

Question 33

movement through the cell walls and the space between cells

Answer 33

apoplast route

Question 34

cytoplasm connected by plasmodesmata

Answer 34

symplast route

Question 35

membrane transport between cells and across the membranes of vacuoles within cells (permits greatest control)

Answer 35

transmembrane route

Question 36

________ and __________ are essential for the bulk transport of minerals

Answer 36

tracheids and vessels

Question 37

over 90% of the plant’s water is lost to the atmosphere through the stomata, _________ and ________ have the greatest effect on the rate

Answer 37

temperature and wind velocity

Question 38

What are some factors that allow plants to limit water loss?

Answer 38

dormancy, loss of leaves, cuticle and wooly trichomes, reducing the number of stomata, having stomata pits on the leaf surface

Question 39

loose parenchymal tissue with large air spaces, collect oxygen, transport O2 to submerged part of the plant, plants have also adapted to life in fresh water

Answer 39

aerenchyma

Question 40

long, spongy, air filled roots that emerge above the mud, lave large lenticels for oxygen entry, secrete salt from their environment (includes mangrove plants)

Answer 40

pneumatophores

Question 41

transport carbohydrates from leaves through rest of plant, move nutrient rich fluid called sap, move sucrose and hormones

Answer 41

phloem

Question 42

the _____________ model describes the movement of carbohydrates in the phloem, flow from the _______ to the _________

Answer 42

source sink model
source
sink

Question 43

What are the steps of phloem-loading? (occurs at the source)

Answer 43

(1) mesophyll makes sugars
(2) active transport of sugars into the phloem causes low water potential
(3) water wants to move into phloem from xylem (more fluid in phloem results, turgor pressure increases)
(4) increased pressure drives the pressure to the sink
(5) once at sink, sugar is then actively transported into cells that need it
(6) water diffuses back into the xylem to be reused