Roots (Quiz 2)

Question 1

Acacia koaia =

not on test

Answer 1

rare dryland Hawaiian tree

Question 2

acacia koaia with

not on test

Answer 2

juvenile (pinnately compound) leaves & phyllodes (sickle shaped)

Question 3

early plants with shoots =

& ex?

Answer 3

no vascular tissue or roots

ex: Aglaophyton

Question 4

early plants (nonvascular/no roots) had (2)

Answer 4

1. ) lateral shoot (below ground = “rhizome”, above ground = “runner”)
2. ) rhizoids (one cell thick)

Question 5

likely precursors to roots =

Answer 5

rhizomes

Question 6

rhizoids homologous to

Answer 6

trichomes

Question 7

Lycopodium =

Answer 7

basal vascular plant w/ roots

Question 8

lycopodium had same body plan as

& whats the main difference between them?

Answer 8

Aglaophyton

& lycopodium exhibits microphylls (leaf with branching veins) and roots!

Question 9

Lycopodium exhibited (2)

Answer 9

1. ) dichotomous branching

2. ) reproductive structures at tips

Question 10

2 basic types of roots:

Answer 10

1. ) adventitious

2. ) Roots from other roots

Question 11

adventitious roots evolved

& develop from

Answer 11

first

the shoots

Question 12

adventitious roots can form

Answer 12

in any group of vascular plants

Question 13

roots from other roots occur in

Answer 13

seed plants

Question 14

roots from other roots develop from

Answer 14

the seed root

• radicle
• other roots develop from the original root

Question 15

root function: (4)

Answer 15

1. ) water & nutrient uptake
2. ) anchoring
3. ) storage
4. ) photosynthesis (some orchids have shoots w/ only flowers & photosynthesize through roots)

Question 16

root zones can be separated

Answer 16

into different zones of development

Question 17

root zones:

& characteristics of them

Answer 17

1. ) zone of cell division (bottom tip) (apical meristem and associative areas)
2. ) zone of elongation (where growth occurs; some tissue differentiation & maturation)
3. ) zone of differentiation (towards base of root) (maturation is where the stele matures and root hairs (aka trichomes) elongate)

Question 18

root hairs function

Answer 18

help in nutrient/water uptake

Question 19

ZOD is where

Answer 19

X, P, & root hairs/trichomes mature

Question 20

root hairs are only found in

Answer 20

the ZOD

Question 21

Root tip structures: (3)

Answer 21

RAM (root apical meristem)
Quiescent center
Root Cap

Question 22

RAM functions

Answer 22

divides to the outside –> root cap

& divides to the inside –> body of the root

Question 23

Root cap functions: (3)

Answer 23

• protection of RAM
• produces mucilage (to prevent desiccation)
• senses gravity (using statoliths)

Question 24

Quiescent center has

Answer 24

dormant (non dividing) stem cells

Question 25

Statoliths are located

Answer 25

in the columella of the root cap

Question 26

statoliths are

Answer 26

specialized amyloplasts that signal the direction of gravity

Question 27

steles are described by

Answer 27

of poles in X

2 = diarch
3 = triarch
4 = tetrarch
5 = pentarch
6 = polyarch

Question 28

Endodermis =

Answer 28

innermost layer of the cortex

Question 29

meta X =

proto X =

Answer 29

new X

old X

Question 30

meta vs proto (transport)

Answer 30

meta cna transport more per cell than proto

Question 31

cortex is made up of

Answer 31

parenchyma

Question 32

endodermis function

Answer 32

produces casparian strip

Question 33

casparian strip forms

Answer 33

on radial walls

Question 34

casparian strip is comprised of

Answer 34

lignin & suberin (sometimes)

Question 35

Types of water movement in steles: (2)

Answer 35

1. ) Apoplastic –> movement along CW’s or intercellular space (can happen from root hairs to X in dicot)
2. ) Symplastic –> movement through cytoplasm “cell - cell” (through channels or plasmodesmata)

Question 36

Pericycle cells =

Answer 36

totipotent

Question 37

Pericycle function: (3)

Answer 37

• produces lateral roots
• produces part of vascular cambium @ X poles
• produces cork cambium

Question 38

roots branch…

Answer 38

endogenously (to protect meristematic tissue)

Question 39

exogenous branching =

Answer 39

w/ axillary buds

Question 40

most roots have no

Answer 40

pith

Question 41

roots w/ pith =

Answer 41

monocots (corn, sugarcane)

Question 42

roots w/ 2* growth exhibit (2)

Answer 42

loss of their cortex

1* P gets pushed out from OG position

Question 43

root types (4)

Answer 43

1. ) taproots –> usually from radicle (dandelion)
2. ) fibrous roots (adventitious) –> usually not in woody plants (grass)
3. ) prop roots (adventitious) –> corn (corn)
4. ) aerial roots (adventitious) –> originated aboveground (orchid)

Question 44

prairie plant roots

Answer 44

are deep, despite herbaceous shoots

Question 45

some prairie plant roots

Answer 45

have long taproot systems

Question 46

many prairie plant roots are

Answer 46

“fibrous”

Question 47

roots produced by stems =

Answer 47

adventitious

Question 48

red mangrove roots grow

Answer 48

down into soil after floating to good location for establishment

Question 49

red mangrove roots can

Answer 49

also produces prop roots w/ loads of air canals (because red mangroves are closest to the ocean)

Question 50

black mangrove roots produce

Answer 50

pneumatophores w/ air canals & lateral roots (to oxygenate roots below water level)

Question 51

black mangroves grow

Answer 51

more inland