Roots 1

Question 1

Major functions of plant roots

Answer 1

anchoring the plant in the soil
absorption of water and nutrients
transport of water and nutrients to the rest of the plant body

Question 2

where do roots originate

Answer 2

formed in the embryo as a radicle when initiated at the root apical meristem

Question 3

2 main patterns for root organization

Answer 3

fibrous root and tap root

Question 4

where do lateral roots develop

Answer 4

from the pericycle in response to chemical signals (plant hormones)

Question 5

where do root hairs develop from

Answer 5

the epidermis

Question 6

root hair function

Answer 6

increase root’s surface area for uptake of water and nutrients

Question 7

where do adventitious roots develop from

Answer 7

from stems and leaves in stem cortical cells

Question 8

roles of water in plant cells

Answer 8

structure (turgor)
cooling
photosynthesis
transport

Question 9

apoplast

Answer 9

water movement outside the cell

Question 10

symplast

Answer 10

water movement within the cell

Question 11

how does water move cell to cell

Answer 11

apoplast and symplast

Question 12

how does water move between organs (vascular tissue)

Answer 12

xylem and phloem

Question 13

how does water move from environment to plant

Answer 13

water uptake and evaporation

Question 14

cell types involved in water movement

Answer 14

vessel elements and tracheids (xylem) (V)
sieve tubes and companion cells (phloem) (V)
roots hairs (D)
guard cells (D)
endodermis (G)

Question 15

roots are adapted to _______ water uptake

Answer 15

maximize

Question 16

Intracellular route of water

Answer 16

via cell interiors, through plasmodesmata (symplast)

Question 17

Extracellular route of water

Answer 17

via cell cells (apoplast)

Question 18

Casparian strip

Answer 18

a hydrophobic barrier in the transverse and radial wall of the endodermal cells

Question 19

how is movement blocked in the apoplast

Answer 19

by the casparian strip

Question 20

osmosis

Answer 20

the movement of water through the semi-permeable membrane from an area of low concentration to one of higher solute concentration

Question 21

water potential

Answer 21

describes the movement of water in plants (move from area of high water potential to area of lower water potential

Question 22

what is an example of what plants do to prevent water loss to the soil

Answer 22

when the soil is dry, the aquaporins close to slow rate of water loss. During prolonged periods of drought, aquaporin gene expression can decrease in the roots.

Question 23

how do solutes move across gradients

Answer 23

the move based on concentration gradients

Question 24

root pressure

Answer 24

if the solute concentration becomes high enough, pressure can develop in the roots, especially when there is a lot of water in the soil

Question 25

what does root pressure do and what is it called

Answer 25

root pressure can drive limited amounts of water from the roots to other parts of the plant
called guttation

Question 26

T/F: guttation (root pressure) is the main mechanism plants use for water uptake or xylem transport

Answer 26

F. It is not the main mechanism