3.3 Xylem, Phloem & transport

Question 1

what does xylem transport?

Answer 1

water and minerals

Question 2

which way does xylem transport water and minerals?

Answer 2

roots to leaves

Question 3

is xylem made of dead or alive tissue?

Answer 3

dead

Question 4

what are dead xylem vessels impregnated with?

Answer 4

lignin for support

Question 5

xylem vessels also have pits what does this do?

Answer 5

let water flow from one xylem to another in case of collapsing

Question 6

what does phloem transport?

Answer 6

sugars

Question 7

in what direction can the phloem transport sugars?

Answer 7

roots to leaves

leaves to roots

Question 8

what does phloem consist of?

Answer 8

companion cells and sieve tube elements

Question 9

is phloem lignified?

Answer 9

no it is a long hollow structure

Question 10

what are sieve tube elements?

Answer 10

cells of the phloem allowing nutrients to flow through the plants in a watery stream

Question 11

how are sieve tube elements arranged in the phloem?

Answer 11

end to end

Question 12

what are companion cells?

Answer 12

cells of the phloem aiding the movement of nutrients

Question 13

what process do plants need to move water for?

Answer 13

photosynthesis

Question 14

the sugars produced in photosynthesis are needed for what and where?

Answer 14

respiration throughout the plant

Question 15

when transporting water and minerals what do the roots hairs give the root?

Answer 15

large surface area for water uptake

Question 16

once in the root water travels from the cortex to where?

Answer 16

vascular tissues in the stele

Question 17

what does the cortex consist of?

Answer 17

undifferentiated parenchyma cells

Question 18

in the xylem water moves through pits to what cells?

Answer 18

elongated tracheid cells

Question 19

how do xylem vessels join to form continuous vessels?

Answer 19

end to end

Question 20

what do sclerenchyma fibres in the xylem provide?

Answer 20

support

Question 21

in the leaf vascular bundles are surrounded by what sort of tissue?

Answer 21

mesophyll tissue

Question 22

what does mesophyll tissue contain?

Answer 22

air spaces into which water evaporates

Question 23

water vapour leaves the plant via the what?

Answer 23

stomata

Question 24

how do stomata control water loss?

Answer 24

opening and closing

Question 25

give an example of the main sugar transported in the phloem?

Answer 25

sucrose

Question 26

what are tubers?

Answer 26

enlarged roots which store sugars by converting them to starch

Question 27

give an example of a tuber:

Answer 27

a potato

Question 28

a tuber grows as a plant is doing what?

Answer 28

photosynthesising

Question 29

when does a tuber break down and why?

Answer 29

to provide sucrose when it is needed for growth

Question 30

phloem consists of sieve tubes supported by what type of cell?

Answer 30

companion cell

Question 31

sieve tubes lack organelles to allow what to move easily?

Answer 31

sap

Question 32

how do fruits store sugars?

Answer 32

by converting them to starch

Question 33

fruits don’t provide energy for the plant, so what do they provide energy for?

Answer 33

the daughter plant

Question 34

fruits also attract animals that do what?

Answer 34

distribute their seeds

Question 35

what type of molecule is lignin, where is it found and what does it do?

Answer 35

carbohydrate found in xylem, providing support

Question 36

what does thick walled xylem parenchyma (tissue) do and contain?

Answer 36

store food

contain tannin deposits

Question 37

(xylem) what is tannin, what does it do?

Answer 37

bitter tasting chemical protecting plant tissues from attack by herbivores

Question 38

(xylem) what can lignin form?

Answer 38

rings
spirals
tubes

Question 39

what do spirals of lignin in the lumen of the xylem help do?

Answer 39

reinforce the xylem vessels so they don’t collapse under transpiration pull

Question 40

which vessels are the main transporting components of phloem?

Answer 40

sieve tube elements

Question 41

(phloem) areas between sieve tube elements become perforated to form what?

Answer 41

sieve plates

Question 42

(phloem) what do sieve plates allow?

Answer 42

phloem contents to flow through