Bio 20B, Chapter 34., The Plant Body

Front 1

root system

Back 1

the organ system that anchors a plant inplace, absorbs water and dissolved minerals, and may store products of photosynthesis from the shoot system

Front 2

shoot system

Back 2

the organ system consisting of the leaves, stem(s), and flowers

Front 3

leaf

Back 3

the chief organ of photosynthesis

Front 4

stems

Back 4

The organ that holds leaves and/or flowers and transports and distributes materials among the other organs of the plant.

Front 5

taproot system

Back 5

a root system typical of eudicots consisting of a primary root (taproot) that extends downward by tip growth and outward by initiating lateral roots.

Front 6

lateral root

Back 6

A root extending outward from the taproot in a taproot system; typical of eudicots

Front 7

taproot

Back 7

an enlarged, somewhat straight to tapering plant root that grows vertically downward. It forms a center from which other roots sprout laterally

Front 8

adventitious roots

Back 8

Roots originating from the stem at ground level or below; typical of the fibrous root system of monocots

[Means arriving from outside]

Front 9

fibrous root system

Back 9

a root system typical of monocots composed of numerous thin adventitious roots that are all roughly equal in diameter

Front 10

phytomer

Back 10

the repeating modules that compose a shoot, each consisting of one or more leaves, attached to the stem at a node; an internode; and one or more axillary buds

Front 11

node

Back 11

a (sometimes enlarged) point on a stem where a leaf is or was attached

Front 12

internode

Back 12

the region between two nodes of a plant stem

Front 13

axillary bud

Back 13

a bud that forms in the angle (axil) where a leaf meets a stem

Front 14

blade

Back 14

the thin, flat portion of a leaf

Front 15

petiole

Back 15

the stalk of a leaf

Front 16

central vacuole

Back 16

a large organelle that stores the waste products of metabolism and maintains turgor

Front 17

tonoplast

Back 17

the membrane of the plant central vacuole

Front 18

middle lamella

Back 18

a layer of polysaccharides that separates plant cells; a shared middle lamella lies outside the primary walls of the two cells

Front 19

primary cell wall

Back 19

a structure that forms at the middle lamella after cytokinesis, made up of cellulose microfibrils, hemicelluloses, and pectins

Front 20

microfibril

Back 20

crosslinked cellulose polymers, forming strong aggregates in the plant cell wall

Front 21

protoplast

Back 21

the living contents of a plant cell; the plasma membrane and everything contained within it

Front 22

secondary cell wall

Back 22

a thick, cellulosic structure internal to the primary cell wall formed in some plant cells after cell expansion stops

Front 23

lignin

Back 23

a complex, hyrophobic polyphenolic polymer in plant cell walls that crosslinks other wall polymers, strengthening the walls, especially in wood

Front 24

meristem

Back 24

plant tissue made up of undifferentiated actively dividing cells

Front 25

suspensor

Back 25

in the embryos of seed plants, the stalk of cells that pushes the embryo into the endosperm and is a source of nutrient transport to the embryo

Front 26

cotyledons

Back 26

A "seed leaf." An embryonic organ that stores and digests reserve materials; may expand when seed germinates

kot-l-eed-n

Front 27

tissue system

Back 27

any of three organized groups of tissues -- dermal tissues, vascular tissue, and ground tissue -- that are established during embryogensis and have distinct functions

Front 28

dermal tissue system

Back 28

the outer covering of a plant, consisting of epidermis in the young plant and periderm in the plant with extensive secondary growth

Front 29

ground tissue system

Back 29

those parts of the plant body not included in the dermal or vascular tissue systems. Ground tissues function in storage, photosynthesis, and support

Front 30

parenchyma

Back 30

A plant tissue composed of relatively unspecializedcell without secondary walls

Front 31

collenchyma

Back 31

A type of plant cell, living at functional maturity, which lends flexible support by virtue of primary cell walls thicked at the corners

Front 32

sclerenchyma

Back 32

A plant tissue composed of cells with heavily thickened cell walls. The cells are dead at functional maturity. The principal types of sclerenchyma cells are fibers and sclereids.

Front 33

fiber

Back 33

In angiosperms, an elongated, tapering sclerenchyma cell, usually with a thick cell wall, that serves as a support function in xylem.

Front 34

sclereids

Back 34

small bundles of sclerenchyma tissue in plants that form durable layers, such as the cores of apples and the gritty texture of pears.

Front 35

vascular tissue system

Back 35

the transport system of a vascular plant, consisting primarily of xylem and phloem

Front 36

xylem

Back 36

In vascular plants, the tissue that conducts water and minerals; xylem consists, in various plants, of tracheids, vessel elements, fibers, and other highly specialized cells

Front 37

phloem

Back 37

in vascular plants, the vascular tissue that transports sugars and other solutes from sources to sinks

Front 38

tracheary elements

Back 38

either of two types of xylem cells--tracheids and vessel elements--that undergo apoptosis before assuming their transport function

Front 39

tracheid

Back 39

a type of tracheary element found in the xylem of nearly all vascular plants, characterized by tapering ends and walls that are pitted but not perforated

Front 40

vessel elements

Back 40

a type of tracheary element with perforated end walls; found only in angiosperms

Front 41

sieve tube element

Back 41

the characteristic cell of the phloem in angiosperms, which contains cytoplasm but relatively few organelles, and whose end walls (sieve plates) contain pores that form connections with neighboring cells

Front 42

determinate growth

Back 42

a growth pattern in which the growth of an organism or organ ceases when an adult state is reached; characteristic of animals and some plant organs

Front 43

indeterminate growth

Back 43

refers to growth that is not terminated

in contrast to determinate growth

Front 44

primary growth

Back 44

growth that is characterized by the lengthening of roots and shoots and by the proliferation of new roots and shoots through branching

Front 45

secondary growth

Back 45

growth that contributes to an increase in girth

Front 46

primary plant body

Back 46

that part of a plant produced by primary growth. Consists of all the nonwoody parts of a plant; many herbaceous plants consist entirely of a primary plant body

Front 47

secondary plant body

Back 47

that part of a plant produced by secondary growth; consists of woody tissues

Front 48

initials

Back 48

cells that perpetuate plant meristems, comparable to animal stem cells. When an initial divides, one daughter cell develops into another initial, while the other differentiates into a more specialized cell

Front 49

apical meristem

Back 49

the meristem at the tip of a shoot or root; responsible for a plant's primary growth

Front 50

lateral meristem

Back 50

either of the two meristems, the vascular cambium and the cork cambium that give rise to a plant's secondary growth

Front 51

primary meristem

Back 51

meristem that produces the tissues of the primary plant body

Front 52

protoderm

Back 52

primary meristem that gives rise to the plant epidermis

Front 53

ground meristem

Back 53

that part of an apical meristem that gives rise to ground tissue system of the primary plant body

Front 54

procambrium

Back 54

primary meristem that produces the vascular tissue

Front 55

root cap

Back 55

a thimble-shaped mass of cells, produced by the root apical meristem, that protects the meristem; the organ that perceives the gravitational stimulus in root gravitropism

Front 56

epidermis

Back 56

in plants and animals, the outermost cell layers (only one layer thick in plants)

Front 57

cortex

Back 57

the tissue between the epidermis and the vascular tissue of a stem or root

Front 58

endodermis

Back 58

a specialized cell layer marking the inside of the cortex in roots and some stems Frequently a barrier to free diffusion

Front 59

stele

Back 59

the central cylinder of vascular tissue in a plant system

Front 60

pericycle

Back 60

in plant roots, tissue just within the endodermis, but outside of the root vascular tissue. Meristematic activity of pericycle cells produces lateral root primordria

Front 61

pith

Back 61

relatively unspecialized tissue found within a cylinder of vascular tissue

Front 62

vascular bundle

Back 62

in vascular plants, a strand of vascular tissue, including xylem and phloem as well as thick-walled fibers

Front 63

vegetative meristem

Back 63

an apical meristem that produces leaves

Front 64

mesophyll

Back 64

chloroplast-containing, photosynthetic cells in the interior of leaves

Front 65

vascular cambium

Back 65

a lateral meristem that gives rise to secondary xylem and phloem

Front 66

cork cambium

Back 66

a lateral meristem that produces secondary growth, mainly in the form of waxy-walled protective cells, including some of the cells that become bark

Front 67

wood

Back 67

secondary xylem tissue

Front 68

periderm

Back 68

the outer tissue of the secondary plant body, consisting primarily of cork

Front 69

bark

Back 69

all tissues external to the vascular cambium of a plant

Front 70

culivar

Back 70

a crop plant variety; a member of a species that has been artifically selected for one or more of its useful traits

Front 71

Svaldbard Global Seed Vault

Back 71

A safe in Norway where seeds are stored.

Front 72

angiosperm

Back 72

flowering plant

Front 73

When did angiosperms first appear?

Back 73

~140 mya

Front 74

About how many angiosperm species exist today?

Back 74

~250,000

Front 75

What are two major features of flower?

Back 75

modified leaves and stems

Front 76

What does vegetative mean?

Back 76

Nonsexual plant parts

Front 77

What three kinds of vegetative organs do angiosperms possess?

Back 77

roots, stems, and leaves

Front 78

morphology

Back 78

the overall form of a plant

Front 79

anatomy

Back 79

the internal component cells and tissues and their arrangement

Front 80

What's the name of the seed vault on the Norweigian island of Spitsbergen?

Back 80

Svalbard Global Seed Vault

Front 81

When did angiosperms first appear?

Back 81

~140 mya

Front 82

How many angiosperm species exist today?

Back 82

~250,000

Front 83

angiosperm

Back 83

flowering plant

Front 84

vegetative

Back 84

nonsexual

Front 85

What are the three kinds of vegetative organs of angiosperms?

Back 85

roots, stems, and leaves

Front 86

morphology

Back 86

the overall form of a plant

Front 87

anatomy

Back 87

the arrangement of a plant

Front 88

What is the chief organ of photosynthesis?

Back 88

leaves

Front 89

What two major clades do angiosperms belong to?

Back 89

monocots and eudicots

Front 90

clade

Back 90

a single "branch" on the "tree of life"

Front 91

monocot

Back 91

generally narrow-leaved flowering plants such as grasses, lilies, orchids, and palms

Front 92

eudicot

Back 92

broad-leaved flowering plants such as soybeans, roses, sunflowers, and maples

Front 93

Which is typically larger, the root system or the shoot system of a plant?

Back 93

the root system

Front 94

radicle

Back 94

the embryonic root of an angiosperm

Front 95

What are the functions of the taproot?

Back 95

often a nutrient storage organ

e.g., in carrots, sugar beets, sweet potatoes

Front 96

monocot roots are generally ____-lived

Back 96

short-lived

Front 97

adventitious roots

Back 97

originating from the stem at ground level or below

Front 98

adventitious roots form:

Back 98

a fibrous root system

Front 99

Why do most fibrous roots have a large surface area?

Back 99

for the absorption of water and minerals

Front 100

What is the central function of stems?

Back 100

To elevate and support the photosynthetic and reproductive organs

Front 101

bud

Back 101

an undeveloped shoot

Front 102

If it becomes active, an axillary bud can develop into a new ________

Back 102

branch, or extension of the shoot system

Front 103

phyllotaxy

Back 103

the arragement of leaves along the stem; often characteristic of the plant species

Front 104

What is the tuber of a potato?

Back 104

It is not a root, but rather an underground stem

Front 105

What are the "eyes" of a potato?

Back 105

depressions containing axillary buds; a sprouting potato is just a branching stem (and not roots)

Front 106

tuber

Back 106

a modified stem

Front 107

tendrils

Back 107

modified portions of leaves that support the plant by wrapping around other structures or plants

seen in peas

Front 108

What distinguishes plants from many other eukaryotic cells (name three)?

Back 108

chloroplasts or other plastids
a central vacuole
Rigid, cellulose-containing cell walls

Front 109

vacuole

Back 109

a watery sac containing a high concentration of solutes, including enzymes, amino acids, and sugars produced by photosynthesis

exerts turgor pressure as it expands

Front 110

purpose of turgor pressure?

Back 110

keeps plants upright and also essential for plant growth

Front 111

Purpose of cell walls?

Back 111

serve to regulate cell volume, determine cell shape, and protect the cell contents

Front 112

sequester

Back 112

to remove or separate.

Front 113

cellulose is made up of:

Back 113

linear polymers of thousands of glucose molecules

Front 114

hemicellulose

Back 114

highly branched polysaccharide chains that extensively cross-link the cellulose microfibrils

Front 115

pectin

Back 115

heterogenous polysaccharides that are more soluble than the other components

(responsible for the gel properties of fruit jam and jellie)

Front 116

How drastically can a cell increase in volume?

Back 116

Some can by 100,000 to 1,000,000 times!

Front 117

The cell wall responds to the increasing size of the protoplast by loosening the linkages between

Back 117

cellulose microfibrils

Front 118

____ cell walls are seen in thick, large stems

Back 118

secondary cell walls

Front 119

What is the most abundant biological polymer on Earth?

Back 119

cellulose

Front 120

What is the second most abundant biological polymer on Earth?

Back 120

lignin

Front 121

TMV

Back 121

tobacco mosaic virus

Front 122

1 ft = ? meters

Back 122

~ 0.3

Front 123

basal-apical axis

Back 123

the arrangement of cells and tissues along the main axis from root to shoot

Front 124

radial xis

Back 124

the concentric arrangement of the tissue systems

Front 125

embryogenesis

Back 125

embryo formation

Front 126

What are the three tissue systems?

Back 126

dermal, vascular, and ground

Front 127

epidermis

Back 127

outer covering

Front 128

periderm

Back 128

the dermal tissue of roots and woody plants

Front 129

three epidermal cell structures:

Back 129

stomatal guard cells

trichomes

root hairs

Front 130

stomatal guard cells

Back 130

form stomata (pores) for gas exchange in leaves

Front 131

trichomes

Back 131

leaf hairs; provide protection against insects and damage from solar radiation

Front 132

root hairs

Back 132

greatly increase root surface area, thus providing more surface for the uptake of water and mineral nutrients

Front 133

stomata

Back 133

pores

Front 134

cuticles are made of?

Back 134

cutin, waxes, et cetera

Front 135

cutin

Back 135

polymer composed of long chains of fatty acids

Front 136

purpose of the cutcle?

Back 136

to limit water loss, reflect solar radiation, and block pathogens

Front 137

Function of ground tissues:

Back 137

storage, support, photosynthesis

Front 138

three ground tissue cell types:

Back 138

parenchyma, collenchyma, schlerenchyma

Front 139

Most common cell type in plants?

Back 139

parenchyma

Front 140

programmed cell death

Back 140

Apoptosis

Front 141

The two types of sclerenchyma cells?

Back 141

fibers
sclereids

Front 142

Which of the ground tissue cells is notable for apoptsis?

Back 142

sclerenchyma

Front 143

What are the two vascular system tissues?

Back 143

xylem

phloem

Front 144

The two types of tracheary elements are:

Back 144

tracheids and vessel elements

Front 145

sessile

Back 145

attached by the base, or without any distinct projecting support, as a leaf issuing directly from the stem.

Front 146

indeterminate growth

Back 146

refers to growth that is not terminated

Front 147

determinate growth

Back 147

where growth stops once a genetically pre-determined structure has completely formed

Front 148

terminal bud contains a _____

Back 148

shoot apical meristem

Front 149

In woody plants, what thickens the stem and root?

Back 149

vascular cambium and cork cambium

Front 150

What cells perpatuate the meristems?

Back 150

The initials

Front 151

What are the two types of meristems?

Back 151

vascular cambium and cork cambium

Front 152

primary growth leads to elongations of ____ and formation of _______

Back 152

elongation of shoots and roots; formation of organs

Front 153

What are the three primary meristem types?

Back 153

protoderm
ground meristem
procambium

Front 154

protoderm leads to what tissue?

Back 154

dermal tissue system

Front 155

ground meristem leads to what tissue?

Back 155

ground tissue system

Front 156

procambrium leads to what tissue systeM?

Back 156

vascular tissue system

Front 157

zone of cell division

Back 157

the source of all the cells of the root's primary tissues

Front 158

zone of cell elongation

Back 158

where the newly formed cells are elongating and thus pushing the root farther into the soil

Front 159

zone of maturation

Back 159

where the cells are differentiating, taking on specialized forms and functions

Front 160

the protoderm gives rise to the ______

Back 160

epidermis

Front 161

cortex

Back 161

a region of ground tissue many cells thick

Front 162

the innermost layer of the cortex is the ________

Back 162

endodermis

Front 163

suberin

Back 163

a waterproof substance found in the endodermal cell walls

Front 164

pith stores

Back 164

carbohydrate reserves

Front 165

shoots are composed of:

Back 165

repeating modules called phytomers

Front 166

shoots grow by:

Back 166

adding new phytomers

Front 167

phtosynthesis involves the exchange of ____ and____

Back 167

O2 and CO2 gasses

Front 168

wood is?

Back 168

secondary xylem

Front 169

cork

Back 169

a protective tissue composed of cells with thick walls waterproofed with suberin

Front 170

lenticels

Back 170

spongy regions in the periderm that allow gas exchange