Plant structure and growth Flashcards
1
Q
What is a tissue?
A
A group of cells consisting of one or more cell types that together perform and specialised function.
2
Q
What is an organ?
A
Something that consists of several types of tissues that together carry out particular functions.
3
Q
What are the three basic plant organs?
A
Roots, stems and leaves.
4
Q
What nutrients do plants absorb below ground?
A
Water and minerals.
5
Q
What nutrients do plants absorb above ground?
A
CO2 and light.
6
Q
What are the functions of the root?
A
Anchoring the plant, absorbing minerals and water and storing carbohydrates.
7
Q
What is the primary root?
A
The first root to emerge from a germinating seed.
8
Q
What is a taproot?
A
A main vertical root.
9
Q
What are lateral roots?
A
They arise from the taproot.
10
Q
What kind of plants have a taproot system?
A
Most eudicots and gymnosperms.
11
Q
What is a fibrous root system?
A
It consists of adventitious roots and lateral roots.
12
Q
What are adventitious roots?
A
They arise from stems or leaves.
13
Q
What types of plants have a fibrous root system?
A
Monocots.
14
Q
Where does absorption of water and minerals occur in most plants?
A
At or near the root hairs as they increase the surface area.
15
Q
What adaptations do prop roots have?
A
Aerial, adventitious roots of corn.
16
Q
What adaptations do buttress roots have?
A
Aerial roots to support the tree.
17
Q
What happens in strangling aerial roots?
A
Seeds of the strangler fig germinate in the branches of tall trees, send aerial roots to the soil. Eventually the host tree dies through shading by fig leaves.
18
Q
What are some storage roots?
A
Sugar beet storage roots store water and sugar.
19
Q
What are pneumatophores?
A
Mangroves produce these negatively geotropic roots to obtain oxygen which is lacking in thick estuarine mud.
20
Q
What is a stem?
A
An organ consisting of an alternating system of nodes - the points at which leaves are attached and internodes, the stem segments between nodes.
21
Q
What is an axillary bud?
A
A structure that has the potential to form a lateral shoot or branch.
22
Q
What is an apical bud?
A
It is located near the shoot tip and causes elongation of a young shoot.
23
Q
What are rhizomes?
A
Horizontal shoots that grow just below the soil surface.
24
Q
What is a stolon?
A
Horizontal shoots that grow along the soil surface and allow asexual reproduction of platelets at nodules along the stolon.
25
What are tubers?
Enlarged ends of rhizomes or stolons for storing food. THe eyes on potatoes are axillary buds.
26
What are bulbs?
Vertical underground shoots that store food.
27
What are leaves?
The main photosynthetic organ of most vascular plants. They consist of a flattened blade and a stalk called the petiole which joins the leaf to a node of the stem.
28
How do monocots and eudicots differ in the arrangement of veins?
Most monocots have parallel veins whereas eudicots have branching veins.
29
What are three different shapes of leaves?
The simple leaf, compound leaf and doubly compound leaf.
30
What is the structure of the compound leaf?
There is a leaflet on the end of the leaf, with an axillary bud and petiole.
31
What is the structure of a doubly compound leaf?
Multiple leaflets.
32
What are the functions of the tendrils?
They are modified leaves that plants use to cling to objects. Once attached the tendril coils pulling the plant closer to the support.
33
What is the function of spines?
They are modified leaves. In the cactus, photosynthesis is carried out in the fleshy green stem.
34
What do storage leaves do?
Store water.
35
What do reproductive leaves do?
THey have adventitious plantlets that fall off and take root in the soil.
36
What are bracts?
Bracts are modified leaves surrounding flowers. Some are brightly coloured and attract pollinators.
37
What is dermal tissue?
A protective layer.
38
What is vascular tissue?
A continuous transport system arranged differently in each organ.
39
What is ground tissue?
Where most metabolic functions take place.
40
What is the dermal system called in a single tissue in nonwoody plants?
The epidermis.
41
What is the purpose of the waxy coating?
The cuticle (waxy coating) prevents water loss from the epidermis.
42
What is protective tissue in woody plants called?
Periderm that replaces the epidermis in olrder regions of stems and roots.
43
What are trichomes?
Outgrowths of the shoot epidermis that can help with insect defense.
44
What is the purpose of the vascular tissue system?
It carries out long distance transport of materials between roots and shoots.
45
What are the two vascular tissues?
Xylem and phloem.
46
What is the function of the xylem?
It conveys water and dissolved minerals upward from roots into the shoots.
47
What is the function of the phloem?
It transports organic nutrients from where they are made to where they are needed.
48
What is the stele?
The vascular tissue of a stem or root.
49
What is the stele in angiosperms?
The solid central vascular cylinder.
50
How is the stele of stems and leaves arranged?
It is divided into vascular bundles, strands of xylem and phloem.
51
What is the ground tissue system?
Tissues that are neither dermal nor vascular.
52
What is pith?
Ground tissue internal to the vascular tissue.
53
What is the cortex?
Ground tissue external to the vascular tissue.
54
What does the ground tissue include?
Cells specialised for storage, photosynthesis and support.
55
What are common types of plant cells?
Parenchyma, collenchyma, sclerenchyma, water-conducting cells of the xylem and sugar-conducting cells of the phloem.
56
What is an organ?
Something that consists of several types of tissues that together carry out particular functions.
57
What are the three basic plant organs?
Roots, stems and leaves.
58
What nutrients do plants absorb below ground?
Water and minerals.
59
What nutrients do plants absorb above ground?
CO2 and light.
60
What are the functions of the root?
Anchoring the plant, absorbing minerals and water and storing carbohydrates.
61
What is the primary root?
The first root to emerge from a germinating seed.
62
What is a taproot?
A main vertical root.
63
What are lateral roots?
They arise from the taproot.
64
What kind of plants have a taproot system?
Most eudicots and gymnosperms.
65
What is a fibrous root system?
It consists of adventitious roots and lateral roots.
66
What are adventitious roots?
They arise from stems or leaves.
67
What types of plants have a fibrous root system?
Monocots.
68
Where does absorption of water and minerals occur in most plants?
At or near the root hairs as they increase the surface area.
69
What adaptations do prop roots have?
Aerial, adventitious roots of corn.
70
What adaptations do buttress roots have?
Aerial roots to support the tree.
71
What happens in strangling aerial roots?
Seeds of the strangler fig germinate in the branches of tall trees, send aerial roots to the soil. Eventually the host tree dies through shading by fig leaves.
72
What are some storage roots?
Sugar beet storage roots store water and sugar.
73
What are pneumatophores?
Mangroves produce these negatively geotropic roots to obtain oxygen which is lacking in thick estuarine mud.
74
What is a stem?
An organ consisting of an alternating system of nodes - the points at which leaves are attached and internodes, the stem segments between nodes.
75
What is an axillary bud?
A structure that has the potential to form a lateral shoot or branch.
76
What is an apical bud?
It is located near the shoot tip and causes elongation of a young shoot.
77
What are rhizomes?
Horizontal shoots that grow just below the soil surface.
78
What is a stolon?
Horizontal shoots that grow along the soil surface and allow asexual reproduction of platelets at nodules along the stolon.
79
What are tubers?
Enlarged ends of rhizomes or stolons for storing food. THe eyes on potatoes are axillary buds.
80
What are bulbs?
Vertical underground shoots that store food.
81
What are leaves?
The main photosynthetic organ of most vascular plants. They consist of a flattened blade and a stalk called the petiole which joins the leaf to a node of the stem.
82
How do monocots and eudicots differ in the arrangement of veins?
Most monocots have parallel veins whereas eudicots have branching veins.
83
What are three different shapes of leaves?
The simple leaf, compound leaf and doubly compound leaf.
84
What is the structure of the compound leaf?
There is a leaflet on the end of the leaf, with an axillary bud and petiole.
85
What is the structure of a doubly compound leaf?
Multiple leaflets.
86
What are the functions of the tendrils?
They are modified leaves that plants use to cling to objects. Once attached the tendril coils pulling the plant closer to the support.
87
What is the function of spines?
They are modified leaves. In the cactus, photosynthesis is carried out in the fleshy green stem.
88
What do storage leaves do?
Store water.
89
What do reproductive leaves do?
THey have adventitious plantlets that fall off and take root in the soil.
90
What are bracts?
Bracts are modified leaves surrounding flowers. Some are brightly coloured and attract pollinators.
91
What is dermal tissue?
A protective layer.
92
What is vascular tissue?
A continuous transport system arranged differently in each organ.
93
What is ground tissue?
Where most metabolic functions take place.
94
What is the dermal system called in a single tissue in nonwoody plants?
The epidermis.
95
What is the purpose of the waxy coating?
The cuticle (waxy coating) prevents water loss from the epidermis.
96
What is protective tissue in woody plants called?
Periderm that replaces the epidermis in olrder regions of stems and roots.
97
What are trichomes?
Outgrowths of the shoot epidermis that can help with insect defense.
98
What is the purpose of the vascular tissue system?
It carries out long distance transport of materials between roots and shoots.
99
What are the two vascular tissues?
Xylem and phloem.
100
What is the function of the xylem?
It conveys water and dissolved minerals upward from roots into the shoots.
101
What is the function of the phloem?
It transports organic nutrients from where they are made to where they are needed.
102
What is the stele?
The vascular tissue of a stem or root.
103
What is the stele in angiosperms?
The solid central vascular cylinder.
104
How is the stele of stems and leaves arranged?
It is divided into vascular bundles, strands of xylem and phloem.
105
What is the ground tissue system?
Tissues that are neither dermal nor vascular.
106
What is pith?
Ground tissue internal to the vascular tissue.
107
What is the cortex?
Ground tissue external to the vascular tissue.
108
What does the ground tissue include?
Cells specialised for storage, photosynthesis and support.
109
What are common types of plant cells?
Parenchyma, collenchyma, sclerenchyma, water-conducting cells of the xylem and sugar-conducting cells of the phloem.
110
What are the properties of mature parenchyma cells?
They have thin and flexible primary walls but lack secondary walls. They have a large central vacuole.
111
What is the function of parenchyma?
They perform the most metabolic functions and are the least specialised. They can differentiate into other types of cells, such as during wound repair.
112
What do parenchyma contain in leaves?
Chloroplasts.
113
What do parenchyma contain in stems and roots?
Colourless plastids that store starch (amyloplasts)
114
What are collenchyma cells?
They support young parts of the plant shoot, without restraining growth.
115
What is the structure of collenchyma cells?
They are grouped into strands and have thicker and uneven cell walls. They lack secondary walls. THey are elongated living flexible cells that are grouped into bundles or layers.
116
What is the structure of sclerenchyma cells?
They are rigid due to thick secondary walls that are strengthened with lignin and are dead at functional maturity.
117
What are the two types of sclerenchyma cells?
Sclereids and fibers.
118
What is the structure of sclereids?
They are short and irregular in shape and have thick lignified secondary walls. They impart hardness to seed coats and nut shells, and texture to pear fruits.
119
What is the structure of fibers?
They are long and slender and are arranged in threads (hemp fibers for string and rope, flax fibers for weaving linen).
120
What happens to xylem cells as they mature?
They die - the cellular contents disintegrates to leave the lignin-hardened cell wall.
121
What are the two types of water-conducting cells?
Tracheids and vessel elements.
122
Where are tracheids found?
The xylem of almost all vascular plants.
123
What plants contain vessel elements?
Most angiosperms and some gymnosperms.
124
What are angiosperms?
A group of plants that contains flowers and produces seeds enclosed within a carpel.
125
What are gymnosperms?
A group of plants that has seeds unprotected by an ovary or fruit.
126
What is the structure of vessel elements?
They are wider, shorter, thinner walled and less tapered than tracheids. The movement of water through them is through perforated end walls.
127
What is the structure of tracheids?
They are long and thin with tapered ends, and the movement of water between them is through pits.
128
What are the sugar conducting cells of the phloem?
Sieve-tube elements.
129
Are sieve-tube elements alive at functional maturity?
Yes, but they lack a nucleus, ribosomes, vacuole and cytoskeleton.
130
What is the purpose in reduction of cell contents of the sieve tube elements?
It allows them to conduct nutrients.
131
What are sieve plates?
Porous end walls that allow fluid to flow between cells along the sieve tube.
132
What is the function of companion cells?
The nucleus and ribosomes serve both themselves and the sieve-tube element. In some plants they load sucrose into the sieve-tube element.
133
What is the function of meristems?
They generate cells for primary and secondary growth.
134
What is indeterminate growth?
The idea that a plant can grow throughout its life.
135
What is determinate growth?
The idea that some plant organs such as leaves and flowers cease to grow at a certain size.
136
What are the two types of meristems?
Apical meristems and lateral meristems.
137
What are the features of apical meristems?
They are located at the tips of roots and shoots and at the axillary buds of shoots. They elongate shotos and roots in a process called primary growth. In non-woody plants primary growth produces most of the plant body.
138
What are the features of lateral meristems?
In woody plants they add thickness to roots and shoots in a process called secondary growth.
139
What are the two types of lateral meristems?
The vascular cambium and the cork cambium.
140
What is the function of the vascular cambium?
It adds layers of vascular tissue called secondary xylem and secondary phloem.
141
What is the function of cork cambium?
It reaplces the epidermis with periderm, which is thicker and tougher.
142
How does primary growth of roots occur?
The root tip is covered by a root cap which protects the apical meristem as the root pushes through soil.
143
What are the zones of cells in which growth occurs?
The zone of cell division, zone of elongation and zone of differentiation/maturation.
144
How do eudicots and monocots differ in xylem and phloem arrangement?
In eudicots root there is xylem and phloem in the centre, whereas in monocots the root has parenchyma in the centre as well.
145
How do lateral roots arise?
From within the pericycle, which is the outermost cell layer in the vascular cylinder.
146
How does primary growth of roots occur?
The root tip is covered by a root cap which protects the apical meristem as the root pushes through soil.
147
What are the zones of cells in which growth occurs?
The zone of cell division, zone of elongation and zone of differentiation/maturation.
148
How do eudicots and monocots differ in xylem and phloem arrangement?
In eudicots root there is xylem and phloem in the centre, whereas in monocots the root has parenchyma in the centre as well.
149
How do lateral roots arise?
From within the pericycle, which is the outermost cell layer in the vascular cylinder.
150
Where do leaves develop in a plant?
From leaf primordia along the sides of the apical meristem.
151
Where do axillary buds develop from?
Meristematic cells left at the bases of lead primordia.
152
What do axillary buds give rise to?
Lateral shoots.
153
How are vascular bundles arranged in eudicot stems?
A ring formation.
154
How are vascular bundles arranged in monocot stems?
Scattered throughout the ground tissue rather than forming a ring.
155
What is a stomata?
A pore that is flanked by two guard cells to be opened and closed. It allows CO2 and O2 to be exchanged between the air and photosynthetic cells.
156
What is the ground tissue in a leaf called?
Mesophyll.
157
What are the two layers of mesophyll in a leaf called?
Palisade mesophyll and spongy mesophyll, which allows for gas exchange.
158
What do vascular bundles do in the leaf?
They support the shape.
159
What are vascular bundles enclosed by?
A protective bundle sheath.
