3.3.1 transport in plants

Question 1

dicotyledonous plants

Answer 1

plants with 2 seed leaves & branching pattern of veins from leaf

Question 2

meristem

Answer 2

layer of dividing cells (pericycle)

Question 3

phloem

Answer 3

transports dissolved assimilates

Question 4

vascular tissue

Answer 4

consists of cells specialised for transporting fluids by mass flow

Question 5

xylem

Answer 5

transports water & minerals

Question 6

why do multicellular plants need a transport system?

Answer 6

1. smaller SA:Vol
2. deliver nutrients & remove waste products
3. different nutrient requirements - eg. autotrophic
4. metabolism in plants is generally slower (than animals)
   - nutrients supplied at lower rate
   - transport system doesn’t need to be as effective
   - no need for pump
   - some nutrients supplied by diffusion eg. photosynthetic gases

Question 7

what does the transport system in plants consist of

Answer 7

specialised vascular tissue

Question 8

name the 2 specialised vascular tissue & what they transport

Answer 8

1. xylem tissue = water & soluble mineral ions travel upwards
2. phloem tissue = assimilates (eg. sugars) travel up OR down

Question 9

describe the distribution of vascular tissue in dicotyledonous plants

Answer 9

• distributed throughout the plant
• xylem & phloem found together in vascular bundles
• bundles may also contain other tissues (eg. collenchyma, sclerenchyma) which give bundle more strength/support plant

Question 10

where is the vascular bundle found

Answer 10

centre of young root

Question 11

describe the structure of the vascular bundle in the root (diagram)

Answer 11

• central core of xylem (often in X shape)
• phloem found between arms of X-shaped xylem tissue
  –> provides strength to withstand pulling forces to which roots are exposed

Question 12

what components are also present around the vascular bundle in the root

Answer 12

• around bundle, special sheath of cells called endodermis
• inside endodermis = layer of meristem cells called pericycle

Question 13

in a plan diagram of a root, where is the medulla located

Answer 13

between central vascular bundle & endodermis

Question 14

endodermis key role

Answer 14

getting water into xylem vessels

Question 15

draw & label plan diagram of a root

Answer 15

pg. 208 of textbook & in class booklet

Question 16

where are the vascular bundles found within the stem

Answer 16

found near outer edge

Question 17

what are the vascular bundles like in non-woody plants

Answer 17

separate & discrete

Question 18

what are the vascular bundles like in woody plants & what does this provide the plant with

Answer 18

bundles are separate in young stems, but become continuous ring in older stems
–> provides strength & flexibility to withstand bending forces to which stems/branches are exposed

Question 19

describe stem plan diagram referring to only phloem and xylem

Answer 19

• xylem found towards inside of vascular bundle
• phloem on outside of vascular bundle
• in between phloem/xylem = cambium

Question 20

what’s the cambium

Answer 20

layer of meristem cells that divide to produce new xylem/phloem

Question 21

phloem consists of

Answer 21

sieve tube element & companion cell

Question 22

draw a plan diagram of a stem

Answer 22

pg 209 in textbook & in class booklet

Question 23

describe leaf plan diagram/structure

Answer 23

• vascular bundles form midrib & veins of leaf
• dicotyledonous leaf has branching network of veins that get smaller as they spread away from the midrib
• each vein = xylem located on top of phloem

Question 24

name components of leaf plan

Answer 24

• xylem & phloem (midrib)
• upper epidermis
• palisade mesophyll
• vein
• spongy mesophyll
• lower epidermis

Question 25

draw leaf plan diagram

Answer 25

pg 209 in textbook & in class booklet

Question 26

medulla/pith in stem plan diagram

Answer 26

medulla/pith = main area surrounding vascular bundles (inside)

Question 27

epidermis in stem plan diagram

Answer 27

epidermis = outer layer

Question 28

collenchyma in stem plan diagram

Answer 28

layer inside epidermis

Question 29

cortex in leaf stem diagram

Answer 29

outside of vascular bundles (borders collenchyma)

Question 30

sclerenchyma in stem plan diagram

Answer 30

outer/third layer of vascular bundle & contains lots of lignin