Midterm Flashcards
1
Q
aDaxial
A
located on the side (of leaf) facing towards the axis
2
Q
aBaxial
A
located on the side (of leaf) facing away from the axis
3
Q
accessory buds
A
an embryonic shoot occurring above or to the side of an axillary bud
4
Q
acropetal
A
produced or becoming differentiated in a succession toward the apex of an organ
5
Q
amphicribral
A
concentric vascular bundle in which the phloem surrounds the xylem
6
Q
amphivasal
A
concentric vascular bundle in which the xylem surrounds the phloem
7
Q
anther
A
the pollen-bearing part of the stamen
8
Q
anthocyanin
A
a water-soluble, blue, purple, or red flavonoid pigment occurring in the cell sap
9
Q
anticlinal
A
having the orientation of the cell wall or plane of cell division perpendicular to the nearest surface
10
Q
apical meristem
A
a group of meristematic cells at the apex of the root or shoot which by cell division produce the precursers of the primary tissues of the root and shoot; may be vegetative, initiating vegetative tissues and organs, or reproductive, initiating reproductive tissues and organs
11
Q
apoplast
A
the interconnected system of plant cell walls
12
Q
astrosclereids
A
a branched sclereid
13
Q
autolysis
A
The destruction of tissues or cells of an organism by the action of substances, such as enzymes, that are produced within the organism
14
Q
axillary bud
A
forms in the axil of a leaf; i.e. just above the point where the leaf joins the stem
15
Q
basipetal
A
produced or becoming differentiated in a succession toward the base of an organ
16
Q
bicollateral
A
a vascular bundle with primary phloem along the inner and outer surfaces of the primary xylem
17
Q
bordered pit
A
two bordered pits opposite each other in adjacent cell walls
18
Q
brachysclereids
A
a short, roughly isodiametric sclereid, resembling a parenchyma cell in shape
19
Q
bract
A
a modified leaf usually subtending a flower or inflorescence
20
Q
bud scales
A
one of the hard protective sometimes hairy or resinous specialized leaves surrounding the buds of certain plants, such as the rhododendron
21
Q
bulb scales
A
one of the leaves of a bulb (as of the lily)
22
Q
bundle cap fibres
A
sclerenchyma or collenchyma appearing in transverse section like a cap on the outer surface of a vascular bundle
23
Q
C3
A
regular carbon fixation, regular leaf anatomy
24
Q
C4
A
carbon fixation with 2 CO2 sources, characterized by Kranz (wreath) anatomy of leaf vascular bundles, large bundle sheath cells with chlorophyll preferentially close to vascular tissues
25
calyx
the sepals collectively, which with the corolla comprise the perianth
26
carotenoids
any of various usually yellow to red pigments (as carotenes) found widely in plants and animals and characterized chemically by a long aliphatic polyene chain composed of eight isoprene units
27
carpels
leaf-like organs in angiosperms enclosing one or more ovules; constituent of the gynoecium, the female part of the flower
28
cataphylls
leaves inserted at low levels of the plant or shoot, as bud scales, rhizome scales, and others
29
cellulose
a polysacchardie, beta-1,4-glucan, the main component of cells walls in most plants; consists of long chain-like molecules, the basic units of which are anhydrous glucose residues of the formula C6H10O5
30
cellulose synthase complex
a cluster of cellulose synthase protein
31
chimera
a plant consisting of a combination of tissues of different genetic composition. In a periclinal chimera, cells of different composition are arranged in periclinal layers
32
chloroplasts
a chlorophyll-containing plastid with thylakoids organized into grana, and embedded in a stroma
33
chromoplasts
a plastid containing pigments other than chlorophyll, usually yellow and orange carotenoid pigments
34
cladophyll
a flattened stem that is leaf-like and green - used for photosynthesis, normally plants have no or greatly reduced leaves
35
collateral
a bundle with phloem on only one side of the xylem, usually the abaxial side
36
collenchyma
a living, supporting tissue composed of generally elongate cells with unevenly thickened non-lignified primary walls. Common in the peripheral regions of stems and leaves
37
companion cell
a parenchyma cell in the phloem of an angiosperm associated with a sieve tube member and originating jointly with the latter from the same mother cell; some have the structure of a transfer cell
38
concentric
a vascular bundle with either the phloem surrounding the xylem (amphicribral) or the xylem surrounding the phloem (amphivasal)
39
confocal
specific type of fluorescence microscopy in which the excitation source is one or more lasers, and allows the possibility of optical sectioning (where layers of tissue can be omitted or scanned deeper based on the focus of the laser)
40
corolla
a collective term for the petals of a flower
41
corpus
the core in an apical meristem covered by the tunica
42
critical point
point at which a liquid becomes a gas and vice versa, for a given temperature and pressure
43
cutin
a complex fatty substance that impregnates cell walls in some plant tissues including the epidermis and which comprises a layer called the cuticle on the outer surface of cell walls
44
desmotubule
tubule connecting the two endoplasmic reticulum cisternae located at the opposite ends of a plasmodesmata
45
determinate
growth of limited duration such as that of leaves, flowers, and other lateral appendages
46
dichroic
type of mirror that allows light of certain wavelength to be transmitted, while other wavelengths are reflected
47
dioecious
Having the male and female reproductive organs borne on separate individuals of the same species
48
distal
farthest from the point of origin or attachment. often used to mean in the direction of the apical meristem
49
emission wavelength
emitted from the sample after excitation in fluorescence microscopy, usually longer than excitation wavelength
50
endodermis
a specialized, single layer of cells enclosing the vascular regions of roots and some stems, the cells of which are characterized by the presence of Casparian bands in the transverse and radial anticlinal walls
51
endoplasmic reticulum
a complex, three-dimensional system of membranes forming tubular or flattened compartments (cisternae) that penetrates the cytoplasm. the cisternae appear like paired membranes in sectional profiles. the membranes may be coated with ribosomes (rough ER) or be free, or nearly free, of ribosomes (smooth ER)
52
epifluorescence
standard compound microscope that is able to incorporate filter cubes and a bright light source in its light path
53
ergastic
passive products of a protoplast; storage or waste products which may be synthesized within a protoplast or transported from other cells
54
eSEM
environmental scanning electron microscopy; does not require coating (or even dehydration), but has lower resolution that SEM
55
etioplasts
in plants which are grown in the dark, chlorophyll does not develop in chloroplasts, so they are called etioplasts
56
excitation wavelength
used to excite a sample in fluorescence microscopy
57
eustele
a stele, lacking leaf gaps, in which the primary vascular tissue comprises axial vascular bundles and leaf traces arranged around a pith. Characteristic of gymnosperms and angiosperms
58
fibre
an elongated, usually tapering, thick-walled cell of the primary and/or secondary xylem. the cell may, but does not always, have a living protoplast at maturity; the cell wall is often lignified
59
filaments
a fine, thread-like structure; also the stalk supporting the anther in a stamen
60
filter cube
filter sets (excitation and emission filters) mounted on a cube that also contains a dichroic mirror
61
fixation
dehydration and embedding in a wax or resin medium, for sectioning
62
fluorochrome
fluorescent molecule that is able to absorb light of one wavelength and emit it at a different (longer) wavelength
63
GFP
Green Fluorescent Protein; originally isolated from jellyfish, and can be fused with genes to show protein (and gene expression)
64
glutaraldehyde
commonly used fixative that acts by cross-linking proteins
65
ground meristem
a transitional meristematic tissue, derived from the apical meristem, which gives rise to the ground tissues
66
gynoecium
collective term for the carpels in an angiosperm flower
67
hemicellulose
a polysaccharide more soluble and less ordered than cellulose; a common component of cell walls
68
hydrophyte
a plant that requires a large supply of water and may grow partly or entirely submerged in water
69
hypogynous
floral condition in which the sepals, petals, and stamens are attached to the receptacle below the ovary
70
hypostomatous
presence of stomata only on the underside (abaxial) of a leaf
71
indeterminate
growth for an indeterminate time, until stopped by other factors (i.e. meristematic growth)
72
intercalary meristem
meristematic tissue derived from the apical meristem located some distance from it and often intercalated between tissues that are no longer meristematic
73
interfascicular meristem
vascular cambium that differentiated between vascular bundles in the interfascicular parenchyma
74
L1, L2, L3
the layers of the apical meristem; L1 and L2 represent the layers of the tunica, while L3 represents the corpus
75
lateral buds
develop laterally to the bud primordium
76
leucoplasts
a colourless plastid; often a site of starch formation
77
lignin
a component of many cell walls which increases their rigidity and resistance to compression; a polymer of high carbon content derived from phenylpropane
78
macrosclereids
elongated, rod-like sclereid with unevenly distributed secondary wall thickenings
79
megasporangium
a sporangium in which megaspores are produced; the nucellus in the ovule in angiosperms
80
meristem
a region of undifferentiated tissue from which, by cell division, new cells are produced
81
mesophyte
plants that require an environment containing moderate levels of soil moisture and a moist atmosphere, in contrast to xerophytes which thrive in dry conditions and hydrophytes which often live in water or soil that remains very wet
82
metaxylem
part of the primary xylem which differentiates after the protoxylem, and usually after cessation of elongation in associated tissues
83
microfibril
a slender strand of cellulose molecules which, with the matrix, are the major components of the cell wall
84
micropyle
the opening in the integuments of an ovule of seed plants through which the pollen grains or pollen tubes usually enter
85
microsporangium
the sporangium in which microspores are formed; the anther locule and its walls in angiosperms
86
microtome
used to section fixed samples (in wax or resin) for microscopy
87
microtubules
slender tubes of indeterminate length, usually straight, with a diameter of about 25nm. they are composed of protein subunits (dimers of alpha and beta tubulin) forming a circle of 13 when observed in transverse section. they occur in the periphery of the protoplast, are closely associated with cellulose microfibrils and also make up the meiotic and mitotic spindles and the phragmoplast
88
middle lamella
a layer of intercellular material, chiefly pectic substances, which cements together the primary walls of contiguous cells
89
mitochondria
a double membrane-bound cell organelle concerned with respiration in eukaryotic cells; the major source of ATP in non-photosynthetic cells
90
monoecious
Having unisexual reproductive organs or flowers, with the organs or flowers of both sexes borne on a single plant, as in corn and pines
91
nectaries
multicellular glandular structures which secrete nectar, a liquid containing organic substances including sugar. Nectaries occur in flowers (floral nectary) and on vegetative plant parts (extrafloral nectary)
92
opposite
pits in tracheary elements disposed in horizontal pairs or in short horizontal rows
93
optical sectioning
in confocal microscopy; laser can be directed to scan deep into the tissue, and can be focused so that it illuminates only that section of the tissue - other layers are not similarly illuminated, and are prevented from emitting out-of-focus, background signals
94
osteosclereids
a bone-shaped sclereid having a columnar middle part and enlargements at both ends
95
ovary
the lower part of a carpel (simple pistil) or of a gynoecium composed of united carpels (compound pistil) containing the ovules, and which will develop into a fruit or part of a fruit
96
ovules
structure in a seed plant enclosing the female gametophyte and composed of the nucellus, one or two integuments, and a funiculus (ovular stalk); differentiates into the seed
97
parenchyma
living cells in which various physiological and biochemical processes occur, usually thin-walled and of variable size and form. Comprise the ground tissue of plant organs
98
pectin
a group of complex carbohydrates, derivatives of polygalacturonic acid, which occur in plant cell walls; major constituents of the middle lamella
99
perfect flower
a flower having both carpels and stamens
100
perianth
petals and sepals of a flower considered together
101
periclinal
having the orientation of cell wall or the plane of cell division parallel with the nearest surface of an organ
102
pericycle
the tissue region located between the primary vascular tissues and the endodermis
103
peripheral thickening
x
104
peripheral zone
x
105
petiole
a leaf stalk supporting a blade and attaching to a stem at a node
106
phloem
the food-conducting tissue of vascular plants which is composed of sieve elements, various kinds of parenchyma cells, fibers, and sclereids
107
phragmoplast
a subcellular structure composed of microtubules that arises between daughter nuclei at telophase and within which the cell plate forms during cell division; appears initially as spindle-shaped, but later spreads laterally in the form of a ring
108
pit
a depression in the cell wall where the primary wall is not covered by secondary wall
109
pit field
x
110
pith
ground tissue in the centre of a stem or root
111
plasmodesmata
highly specialized regions of endoplasmic reticulum that extend through cell walls and connect the protoplasts of adjacent cells
112
plastids
an organelle with a double membrane in the cytoplasm of many eukaryotes. may be the site of photosynthesis (chloroplast) or starch storage (amyloplast), or contain yellow or orange pigments (chromoplast)
113
pollen tube
a tubular cell extension formed by the germinating pollen grain; carries the male gametes into the ovule
114
primary tissue
tissues derived from the apical meristem and the transitional tissue regions, protoderm, ground meristem, and provascular tissue; contrasting with secondary tissues derived from lateral meristems such as the vascular cambium and the phellogen
115
primordium
a cell or organ in an early stage of diffrentiation
116
prolamellar bodies
composed of tubular membranes with comprise a paracrystalline lattice, and characterize etioplasts
117
prostrate
growing flat along the ground
118
protoplast
the organized living unit of a single cell excluding the cell wall
119
protostele
the simplest type of stele, containing a solid column of vascular tissue, with the phloem peripheral to the xylem
120
protoxylem
the first formed cells of the primary xylem in a plant organ
121
provascular
the transitional tissue region, partly meristematic, from which the primary vascular tissue differentiates
122
proximal
situated near the point of origin or attachment. often used to mean in a direction away from the apical meristem (i.e. toward the base of the plant)
123
pulvinous
the swollen base of a petiole or petiolule usually involved in leaf movements and leaf orientation
124
rachis
main axis of a compound leaf (also the axis of an influorescence)
125
radial
developing symmetrically about a central point
126
receptacle
the part of the flower stalk that bears the floral organs
127
residual meristem
a meristematic region in the shoot apex, below the apical meristem in some taxa, in which provascular strands develop
128
reticulate
pattern of venation in a leaf blade in which the veins form an anastomosing system, the whole resembling a net
129
rib meristem
a meristem in which the cells divide perpendicular to the longitudinal axis of an organ and produce a complex of parallel, vertical files of cells; particularly common in ground meristem of organs that are of cylindrical form
130
rosette
cluster of leaves with very short internodes that are crowded together, normally on the soil surface but sometimes higher on the stem; also describes a type of cellulose synthase complex
131
S1, S2, S3
layers of the secondary cell wall, characterized by varying orientations of microfibrils and thickness
132
SAM
shoot apical meristem
133
scalariform
in tracheary elements, secondary wall depositions on the primary wall in a ladder-like pattern.
134
schlerenchyma
cell of variable form and size having more or less thick, often lignified, secondary walls; belongs to the category of supporting cells and may or may not be devoid of a protoplast at maturity
135
secondary tissue
tissues produced by the vascular cambium and phellogen during secondary growth
136
secondary wall
the inner layer of the wall deposited upon the primary wall after cell growth (increase in size) has ceased
137
SEM
scanning electron microscopy
138
sepals
a unit of the calyx, can be photosynthetic
139
sieve cells
sieve element that has sieve areas, usually with sieve pores of small diameter, on all walls; there are no end wall sieve plates. typical of gymnosperms and seedless vascular plants
140
sieve plate
the part of the cell wall (usually the end walls) of a sieve element bearing one or more highly differentiated sieve areas typical of angiosperms
141
sieve tube member
one of a series of cell components of a sieve tube. characterized by sieve plates on the end walls and less highly differentiated lateral sieve areas
142
simple pit
a pit in a secondary wall which lacks an overhanging border
143
sporophyte
the diploid (2n) phase which produces spores in a life cycle characterized by alternation of generations
144
sputter coating
coating of a thin layer of metal (e.g. gold) on samples used for SEM to increase surface conductivity and signal/noise ratio
145
stamens
floral organs which produce the phloem and are usually composed of anther and filament. collectively the stamens constitute the androecium
146
starch grains
bodies of accumulated starch, an ergastic substance. begin development in amyloplasts, and are composed of concentric layers of starch around a hilum (site of starch synthesis)
147
stigma
the region of the carpel, usually at the apex of the style, that serves as a surface upon which the pollen germinates
148
stipules
One of the usually small, paired appendages at the base of a leafstalk in certain plants, such as roses and beans
149
Stokes shift
the difference between absorption and emission wavelengths
150
striate
striped, grooved, or ridged
151
style
an extension of the ovary, usually columnar, through which the pollen tube grows
152
suberin
fatty substance in the cell walls of cork (phellum) cells and in the casparian band of endodermal and exodermal cells
153
symplast
the living protoplasts of all cells in an organism, or a region of an organism, and the plasmodesmata by which they are connected
154
tangential
a longitudinal section cut at right angles to a radius of a cylindrical structure such as a stem or root. a tangential section of secondary wood or secondary phloem is cut at right angles to the rays
155
tannins
a heterogenous group of phenol derivatives; amorphous, strongly astringent substances widely distributed in plants, and used in tanning, dyeing, and preparation of ink
156
TEM
Transmission Electron Microscopy
157
tracheary element
a water-conducing cell, tracheid, or vessel member
158
tracheid
an elongate tracheary element of the xylem with tapered or rounded ends, and having no perforations, as contrasted with a vessel member; may occur in primary and secondary xylem
159
transfer cells
a parenchyma cell with wall ingrowths that increase the surface of the plasmalemma which lines the wall surface. Specialized for short distance, apoplastic transfer of solutes
160
tunica
peripheral layer or layers of an apical meristem of a shoot, the cells of which divide anticlinally and thus contribute to the growth in surface of the meristem. forms a mantle over the corpus
161
vessel member
a non-living, conducting cell of the xylem characterized by perforations in the contiguous end walls of superposed cells that form a vessel. Vessel members function in the transport of water and minerals through the primary and secondary xylem of angiosperms
162
whorled
a collection of three or more leaves or flowers that arise from the same point
163
xerophyte
a plant adapted to a dry habitat
164
xylem
a complex tissue of parenchyma and tracheary elements that functions in the longitudinal transport of water and minerals. in secondary xylem, rays function in radial transport. the xylem is also a supporting tissue
165
xyloglucan
x
166
xylose
x
