Unit 3 Flashcards
(126 cards)
1
Q
Embryo
A
A young, developing plant
2
Q
Cotyledon
A
seed leaves
3
Q
Seed coat
A
product of the integuments
4
Q
Plumule
A
embryonic shoot/stem
5
Q
Radicle
A
embryonic root
6
Q
Scutellum
A
single cotyledon
7
Q
Coleorhiza
A
the sheath investing the radicle in some monocotyledonous plants through which the roots emerge
8
Q
Epicotyl
A
the portion of the axis of a plant embryo or seedling above the cotyledonary node
9
Q
Hypocotyl
A
all parts of the embryo under the cotyledons
10
Q
Primary meristems
A
protoderm, ground meristem, procambium
11
Q
Protoderm
A
dermal tissue
12
Q
Ground meristem
A
ground tissue
13
Q
Procambium
A
vascular tissue
14
Q
Apical meristem
A
region of cells capable of division and growth in the root and shoot tips in plants, does primary growth
15
Q
Lateral meristem
A
a meristem that is arranged parallel to the sides of an organ and that is responsible for increase in diameter of the organ, does secondary growth
16
Q
Primary growth
A
-plants get taller (stems and roots)
-elongation of the root and shoot apical meristems
17
Q
Secondary growth
A
-plants get wider
-elongation of the root and shoot lateral meristems
18
Q
Seed dormancy
A
the state in which seed is unable to germinate, even under ideal growing conditions
19
Q
Taproot
A
elongation of the radicle
20
Q
Branch/lateral roots
A
extend from center vascular tissue
21
Q
Fibrous roots
A
radicle dies, stem produces roots
22
Q
Adventitious roots
A
roots produced by the stem
23
Q
Root cap
A
protects root atypical meristem
24
Q
Zone of cell division
A
apical and primary meristems
25
Zone of elongation
-weaken cell wall to allow elongation
-pressure in central vacuole decreases as cell elongates, allowing cell wall to weaken
-cells elongate, moving the root deeper
26
Zone of maturation
differentiation
27
Epidermis
plant skin, outer protective layer
28
Cortex
ground tissue
29
Pith
a usually continuous central strand of spongy tissue in the stems of most vascular plants that probably functions chiefly in storage
30
Stele/vascular cylinder
running down middle of plant
31
Pericycle
inner dermal structure surrounding stele, produces lateral roots
32
Endodermis
outer dermal structure surrounding stele
33
Xylem
transports water and minerals
34
Phloem
transports food and nutrients
35
Casparian strip
a cellular feature found in the roots of all higher plants; occur in the endodermis, an inner cell layer that surrounds the central vascular strand of roots
36
Aerial roots
any root exposed to the air
37
Prop roots
any root supporting a plant
38
Pneumatophores
an aerial root specialized for gaseous exchange
39
contractile roots
responsible for movement of the underground shoot part ofthe plant, e.g., a corm, a bulb, or a rhizome
40
Haustoria
a slender projection from the root of a parasitic plant, such as a dodder, or from the hyphae of a parasitic fungus, enabling the parasite to penetrate the tissues of its host and absorb nutrients from it
41
Herbaceous shoots
vascular plants that have no persistent woody stems above ground
42
Herbaceous shoots
vascular plants that have no persistent woody stems above ground
43
Woody shoots
44
Annual
Plants that perform their entire life cycle from seed to flower in a year, then die
45
Biennial
Plants which require two years to complete their life cycle
46
Perennial
plants that can live for three or more growing seasons
47
Node
where leaves and branches attach on the main stem
48
Internode
stem parts between nodes
49
Axil
angle between a branch leaf and main stem
50
Axillary bud
bud within the axil
51
Phylotaxy
arrangement of leaves at a node
52
Alternate phylotaxy
1 leaf per node
53
Opposite phylotaxy
2 leaves per node
54
Whorled phylotaxy
3+ leaves per node
55
Stolon
above ground horizontal stems
56
Rhizome
below ground horizontal stems
57
Tuber
storage structures at the end of stolons/rhizomes
58
bulb
storage structures in modified leaves
59
Corm
vertical, fleshy, underground stem that acts as a food-storage structure in certain seed plants
60
Petiole
the stalk that joins a leaf to a stem
61
Blade
flattened part of leaf
62
Midrib
spine down center of leaf
63
Veins
vascular tissue running through leaf
64
Margin
edge of the leaf
65
Cuticle
an extracellular hydrophobic layer that covers the aerial epidermis of all land plants
66
Stomata
pores in lower epidermis
67
Stoma
a circular pore with a hole in the middle for gas to enter or leave the plant
68
Guard cells
open/close stomata
69
Palisade mesophyll
upper mesophyll
70
Spongy mesophyll
lower mesophyll
71
Vascular bundles
a strand of conducting vessels in the stem or leaves of a plant, typically with phloem on the outside and xylem on the inside
72
Bundle sheath
cells surrounding vascular bundle
73
Parallel veination
a leaf whose veins run in parallel from the stem
74
Netted veination
Veins in a branching pattern
75
Simple leaf
1 blade per petiole
76
Pinnately complex leaf
leaves branch out in a ladder pattern from the petiole
77
Palmately complex leaf
leaves branch out in a radial patterm from the petiole
78
Deciduous
loses leaves every fall
79
Evergreen
leaves never fall
80
Leaf abscission
part between stem and petiole
-weaken this area and let the weight of the leaf pull it off
81
C3 photosynthesis
- typical photosynthesis
- consists of light-dependent reaction (splits water into ions, uses ions to make ATP), and light-independent reaction (can occur with/without light, uses energy from ATP/NADH to make sugar from CO2)
82
C4 Photosynthesis
carbon is stored as a 4-carbon compound
- seen in grassses
83
CAM photosynthesis
- (Crassulacean Acid Metabolism)
- temporal change to photosynthesis
- normal in arid environments
- day: stomata closed, absorb light, remove CO2 stored from night before in bundle sheath cells and make sugar
- night: stomata open, CO2 in, stored as a 4-carbon compound in the bundle sheath cells, transpiration
84
Vascular cambium
produces secondary phloem to the outside and secondary xylem to the inside
85
Primary xylem and phloem
produced in the first year of growth
86
Secondary xylem and phloem
produced after the first year of growth
87
secondary xylem
- adds more water-conducting tissue, which expands the plants' capacity to transport water from the roots
- replaces old xylem
-adds structural support (wood)
88
secondary phloem
- increases the plant's capacity to transport sugars from the leaves
replaces old phloem
89
Periderm
outer bark (cork, cork cambium, phelloderm)
90
Phelloderm
a layer of thin-walled cells produced by the inner surface of the cork cambium
91
Cork
The outer protective coat of a tree
92
Inner bark
secondary phloem (and primary, if present)
93
Outer bark
periderm (cork, cork cambium, phelloderm)
94
Fusiform initial
an elongated tapering cell in the cambium that through repeated division gives rise to vertically arranged cells
95
Periclinal cell division
the ones that occur parallel to the tissue or organ surface
96
Ray initials
cells that remain in the meristematic region after cellular division
97
Anticlinal cell division
produces 2 cambial cells
- makes rings
98
Xylem and phloem rays
complex tissues that perform transportation of food and water in a plant
99
Heartwood
dead, central wood of trees
100
Sapwood
outer, living layers of the secondary wood of trees, which engage in transport of water and minerals to the crown of the tree
101
Spring wood
the softer more porous portion of an annual ring of wood that develops early in the growing season
102
Summer wood
The wood in a tree's growth ring formed later in the growing season, when growth is less rapid
103
Dendrochronology
the science that deals with the dating and study of the annual growth increments, or tree rings, in woody trees and shrubs
104
Reaction wood
wood that forms in place of normal wood as a response to gravity, where the cambial cells are oriented other than vertically. It is typically found on branches and leaning stems. It is an example of mechanical acclimation in trees.
105
Hormone
molecules that are sent from 1 cell to another to initiate a response
106
Auxin
a. produced in the shoot apical meristems, young leaves, and embryos
b. transported through the phloem parenchyma
c. functions:
- stimulates cell growth (stem + root)
* stimulates proteins to pump H+ into the cell walls
* ions activate the expansion enzymes
* expansins weaken cell walls, allowing for elongation
* reduce the resistance in cell walls, allowing water to flow by osmosis, therefore expanding the cell
* auxin levels drop as IAA oxidase destroys it
- responsible for the development of lateral meristems
-involved in apical dominance
-regulates the development of fruit
107
Cytokinins
a. synthesiszed in the roots + are transported elsewhere, but can also be produced in the stems, leaves, and seeds
b. controlls cell division and differentiation
c. counteracts apical dominance by stimulating axillary bud growth
d. delays aging of leaves
e. stimulates germination
108
Gibberellins
a. synthesized in the apical meristems, leaved, and embryos
b. involved in stem elongation by helping expansins move into their correct positions in the cell wall, and also increases cellular concentrations of auxin
c. aid in seed germination and gmebryo growth (promotes breakdown of starch)
d. promotes flowering
109
Abscisic acid
a. synthesized in the leaves, stems, roots, and green fruits
b. establishes seed dormancy by preventing germination in cold temperatures
c. helps the plant adapt to water stressby closing stomata
110
Ethylene
- gas
a. synthesized in fruits, roots, stems, leaves, and flowerbuds
b. causes responses to mechanical stress
c. aids in fruit ripening and leaf abscission
represses vertical growth and stimulates horizontal growth (wind/stress)
e. aids in growth to move around obstacles
111
Brassinosteroids
a. synthsized in the seeds, fruits, shoots, leaves, and flower buds
b. stimulates cell division and elongation in stems like auxin)
c. causes differentiation in the xylem
d. promotes pollen tube growth
e. slows root growth
f. delays leaf abscission
112
Tropism (negative vs positive)
plant responses to external stimuli
- positive tropism - towards stimulus
- negative tropism - away from stimulus
113
Phototropism
- tropism of light
114
Gravitotropism
gravity
- shoots: negatively gravitotropic
- roots: positively gravitotropic
115
Statolith hypothesis
solid objects in the cytoplasm fall towards the gravitational pull
116
Gravitational pressure hypothesis
gravitational pressure hypothesis: stretching of proteins in the cell membrane
117
Thigmotropism
pressure differences or touch
- ex: venus flytrap has hairs on the leaf that are triggered by the change in pressure (cells contract with turgor pressure)
118
Hydrotropism
water tropism
119
Heliotropism
sun tropism
120
Chemotropism
chemical tropism
121
Apoplastic transport
water flows between cells
122
Symplastic transport
water flows inside cells, along cell walls, and outside central vacuoles
123
Transcellular transport
water flows inside cellls, central vacuole to central vacuole
124
Pressure flow hypothesis
water containing food molecules flows under pressure through the phloem
- high pressure at the top and low pressure at the bottom keeps the water/sugar (sap) moving
125
Micronutrients
essential plant nutrients that are found in trace amounts in tissue, but play an imperative role in plant growth and development
126
Macronutrients
nutrients required by the plants in large amounts (carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur, calcium and potassium)
