LO9 Flashcards
(157 cards)
1
Q
What do plants need that they acquire via their shoot system
A
light and CO2
2
Q
What is the main photosynthetic organ of a plant?
A
leaves
3
Q
How does the structure of a leave allow it to efficiently absorb light and CO2`
A
large surface area; broad and thin
4
Q
What are two functions of stems?
A
- support leaves
- carry out photosynthesis
5
Q
What do plants need that they acquire from their root system?
A
- H2O
- O2
- minerals from soil
6
Q
definition: roots that are adapted to obtain water from deep underground
A
taproots
7
Q
definition: roots adapted to obtain water from a large surface area of soil close to the surface
A
fibrous roots
8
Q
What kind of stems and roots do herbaceous plants have?
A
soft green
9
Q
What do herbaceous plants never produce?
A
wood and bark
10
Q
Herbaceous life cycle are
A
annuals or perennials
11
Q
Herbaceous perennials have aboveground parts that do what in the winter?
A
die
12
Q
How many tissues are vascular plants made up on?
A
three
13
Q
What are the three vascular plant tissues?
A
ground, vascular, and dermal
14
Q
What are three roles of ground tissue?
A
- photosynthesis
- storage
- structural support
15
Q
What are two roles of vascular tissue
A
- conduction
-support
16
Q
What are two roles of dermal tissue?
A
- reduces water loss
- protects plants against pathogens
17
Q
The most abundant tissue in plants is??
A
ground tissue
18
Q
What tissue is only found on the outside of the plant body?
A
dermal tissue
19
Q
What are three functions of parenchyma cells?
A
- photosynthesis
- secretion
-storage
20
Q
What are the names of the three ground tissue cells?
A
parenchyma, collenchyma, sclerenchyma
21
Q
Why are parenchyma cells not suited to structurally support a plant?
A
- no secondary wall
- thin primary cell wall
22
Q
What is one function of collenchyma cells?
A
flexible support
23
Q
What is one way collenchyma are structurally adapted for this role?
A
thicker primary cell wall
24
Q
What is one function of sclerenchyma cells?
A
- hard inflexible support
25
Which substances are transported in tracheids and vessel elements?
water and minerals
26
Which process causes tracheids and vessel elements to dies once they reach maturity?
apoptosis
27
Which plants have tracheids?
vascular plants
28
Which plants have vessel elements
angiosperms only
29
What are the two tissue types of vascular tissue?
xylem and phloem
30
definition: forms hollow channels that transport water and minerals from the roots to the shoots
xylem tissue
31
What are the state of xylem cells at maturity?
they are dead due to apoptosis
32
What are the two types of xylem cells?
tracheids and vessel
33
definition: are tapered xylem cells
tracheids
34
definition: are wider xylem cells
vessel
35
How does water move in tracheids
laterally through pits
36
How does water move in vessel elements
vertically through end perforations and laterally through pits
37
definition: forms channels that transport organic molecules produced by photosynthesis
phloem tissue
38
What do sieve tube elements do?
join end-toend to form long tubes
39
Are sieve tube elements alive at maturity?
yes
40
This protects herbaceous plants
epidermis
41
definition: a single layer of non-photosynthetic, transparent flattened cells
epidermis
42
What do epidermal cells of leaves and stems secrete?
a waxy cuticle
43
What is the epidermis perforated by?
the stomata
44
definition: regulate the opening and closing of the pore?
photosynthetic guard cells
45
How many photosynthetic guard calls surround the stoma pore?
two
46
Which layer of a woody plant is formed by the periderm?
outer bark
47
Which type of cells make up the peridem?
non-living cork cells
48
What happens to the epidermis of the stems and roots in mature woody platns?
it is replaced by a tougher peridem
49
What are cork cell walls reinforced with?
a waxy waterproof materiel`
50
definition: tissue that is made of stem cells that divide as long as the plants is alive
meristem
51
what parts of the plant have indeterminate growth?
stem and roots
52
What parts of the plant have determinate growth?
leaves and flowers
53
What is primary growth
increase in length of stems and roots
54
Which plants have primary growth?
woody plants and herbaceous
55
which plants ONLY have primary growth?
herbaceous
56
Which plant tissues allow for primary growth
- apical meristems
57
where are apical meristems located?
- tip of roots and stems
58
What is secondary growth?
an increase in girth in woody plants
59
Which plant tissues allows for secondary growth?
lateral meristems
60
Where are lateral meristems located?
sides of stem and roots
61
Which plants have secondary growth?
- gymnosperms
-woody angiosperms
62
What does vascular cambium produce?
secondary vascular tissues
63
secondary xylem = _____
wood
64
secondary phloem = ________
the living inner bark
65
Cork cambium produces what?
periderm
66
What is transpiration?
water evaporation
67
which part of the plant body is responsible for transpiration?
leaves through the stomata
68
What process is transpiration necessary
drives water and mineral transport
69
What causes wilting?
plants lost more water than they can absorb through their leaves
70
What is occuring at the cellular level when a plant is wilted?
the cells are losing turgor pressure
71
What happens to a deciduous tree leaves during the winter?
it looses it leaves
72
definition: process by which trees shed their leaves
leaf abscission
73
Why do some trees shed their leaves to prepare for winter?
to conserve minimal amounts of water available
74
What causes leaves to change color right before they fall off of a tree?
chlorophyll in the leaves break down
75
when are stomata typically open?
during the day
76
why are stomata open during the day
so that CO2 can enter when light is available
77
when are stomata typically closed?
at night
78
why are stomata typically closed at night?
photosynthesis isnt occuring and to prevent water loss
79
Guard cells bulge and separate from one another, opening stomata when they __________?
gain water
80
Guard cells gain water in the __________ as ion pumps are activated by light
morning
81
What happens to the ion concentration inside of guard cells when they gain water?
it increases
82
The ion concentration increasing results in water moving ________ the guard cells via osmosis
into
83
what does the epidermis that is covering leaves and herbaceous stems have?
cuticle, guard cells, and stomata
84
What fills most of the intrior of a leaf steam
ground tissues and parenchyma cells
85
In stems what do parenchyma, collenchyma, and sclerenchyma cells doe?
store starch, support the stem
86
What are herbaceous roots covered by?
epidermis with root hairs
87
what do root hairs do?
increase surface area for water absorbtion
88
definition: protects the delicate apical meristem
root cap
89
What are four examples of plant primary tissues
epidermis, ground tissue, primary xylem, phloem
90
what are the two types of secondary tissues
wood and bark
91
once secondary growth begins, do woody plants still have primary growth at their apical meristems?
yes
92
What are the two types of lateral meristem tissues?
cork and vascular
93
apart from at their tips, the interior of woody stems and roots are filled with mostly what type of tissue?
secondary xylem
94
when woody plants age what happens to most of their primary tissues?
they are replaced by secondary tissues
95
definition: produces cork cells to replace the epidermis with periderm
cork cambium
96
definition: produces secondary xylem and secondary phloem to replace primary xylem, primary phloem, and ground tissue
vascular cambium
97
What are older woody stems and roots mostly made of?
secondary xylem
98
Which type of secondary tissue is involved in forming annual tree rings?
secondary xylem cells
99
during which season are secondary xylem cells produced with a larger diameter
spring
100
when are secondary xylem cells produced with a narrower diameter
summer
101
definition: form due to differences in size of secondary xylem cells produced during different seasons in temperate climates
annual rings
102
How is an annual ring created?
when there is differences in diameter between the summerwood and the springwood
103
What happens during xylem transport
roots absorb water + minerals from the soil and transport it upwards
104
Do plants expend energy during xylem transport
no
105
Explain the tension-cohesion model?
- leaves lose water and tension pulls the water from the stem
- then water is then pulled from the roots into the stem
- and water from the soil into the roots
106
what does tension result from in the stem?
transpiration at the leaves
107
What causes water molecules to form a continuous chain (cohesion) from the soil to the leaves
hydrogen bonding
108
during phloem transport what is happening?
phloem sap is translocated in sieve tube elements
109
definition: mostly sucrost but is also contains some amino acids and hormones
phloem sap
110
How does phloem sp flow?
in any direction but away from a source to a sink
111
definition: mature leaves that carry out photosynthesis and also storage roots that can break down starch
sources
112
roots, meristem tissue, developing leaves, fruits and seeds are examples of?
sinks that need sugar
113
exmaples of sugar sources
mature leaves, and storage roots
114
what does the pressure flow model explain
phloem transport
115
during the pressure flow model what happens?
- phloem sap is loaded into sieve tube elements at leaves
- because of high sugar concentration at the source water moves into sieve tube elements
- this buildup creates a pressure gradient
- which causes a push of phloem sap to the lower pressure sink
116
does translocation require energy?
no
117
does loading and unloading sucrose at the source and sink require eneryg?
yes ATP
118
the cells of this are packed tightly together and have a waxy, impenetrable layer in their cell walls
endodermis
119
definition: waxy impenetrable layer
casparian strip
120
Water and mineral cannot enter root xylem without crossing a layer of cells called what?
endodermis
121
definition: a subterranean association between plant roots and fungi that enhances absorption
mycorrhize
122
What does the plant supply to the fungus and what does the fungus supply to the plant
plant provided organic nutrients to the fungus
fungus absorbs water and minerals from the soil
123
what plants mostly have mycorrhize?
vascular plants
124
definition: house rhizobial bacteria that fix nitrgoven
root nodules
125
definition: modified leaves that protect agains herbivores and conserve water
spines
126
definitions: has underground storage leaves
bulb
127
what doe storage leaves and roots do?
they store food and/or water
128
definition: use their leaves to trap food to supplement nitrogen lacking in their soil
carnivorous
129
definitions: plants that use aerial roots to attach to other plants
epiphytes
130
examples of epiphytes
orchids
131
definition: epiphytes that have aerial roots that penetrate host tissues
parasitic epiphytes
132
definition: the ability of an organism to change its physical features in response to differenct environmental conditions
plasticity
133
definition: growth towards away from a stimulus
tropism
134
definition: a directional growth caused by light
phototropism
135
definition: a directional growth in response to gravity
gravitropism
136
What kind of gravitropism do the stem and root tips
stems - neg gravitropism
root - pos gravitropism
137
definitions: auxins and gibberellic acid both contribute to stem elongation
overlapping hormones
138
definition: abscisic acid promotes seed dormancy, while gibberellic acid promotes seed germination
antagonistic hormones
139
For antagonistic hormones the ration of the hormones determines what?
whether the seed will germinate or not
140
definition: promotes cell elongation
auxins
141
definition: causes acidification of plant cell walls increasing their flexibility and allowing them expand
auxins
142
This hormone causes a positive phototrophic response
auxin
143
What happens when a stem is exposed to light?
auxin migrate to the shaded side of the stem
144
definition: a gas that promotes fruit ripening and leaf abscission
ethylene gas
145
definition: promotes seed dormancy and closes stomata in drought conditions
abscisic acid
146
are able to detect light due to this
photoreceptors
147
definition: help plants track changes in day an dnight length
phytochromes
148
phytochromes are activated by what in the sunlight
the red light
149
phytochromes are inactivated by what in the moonlight
far-red light
150
what are examples of photoperiodic
flowering, seed germination, leaf abscission
151
definition: regulate 24 hr plant responses
circadian rhythms
152
what operates on a 24 hr circadian cycle
rate of photosynthesis and the opening and closing on a circadian cycle
153
what keeps circadian rhythms constant
daily light and dark cycles
154
definitions: are blue light absorbing photoreceptors
cryptochrome
155
what resets the biological clock each day
phytochromes and cryptochromes
156
definitions: regulate daily activities
circadian rhythms
157
definitions: regulates seasonal activities
photoperiodisms
