Openstax Biology - Chapter 30 - Plant Form & Physiology

Front 1

meristem

Back 1

plant region of continuous growth

Front 2

meristematic tissue

Back 2

tissue containing cells that constantly divide; contributes to plant growth

Front 3

negative gravitropism

Back 3

growth away from Earth’s gravity

Front 4

node

Back 4

point along the stem at which leaves, flowers, or aerial roots originate

Front 5

oligosaccharin

Back 5

hormone important in plant defenses against bacterial and fungal infections

Front 6

palmately compound leaf

Back 6

leaf type with leaflets that emerge from a point, resembling the palm of a hand

Front 7

parenchyma cell

Back 7

most common type of plant cell; found in the stem, root, leaf, and in fruit pulp; site of photosynthesis and starch storage

Front 8

pericycle

Back 8

outer boundary of the stele from which lateral roots can arise

Front 9

periderm

Back 9

outermost covering of woody stems; consists of the cork cambium, cork cells, and the phelloderm

Front 10

permanent tissue

Back 10

plant tissue composed of cells that are no longer actively dividing

Front 11

petiole

Back 11

stalk of the leaf

Front 12

photomorphogenesis

Back 12

growth and development of plants in response to light

Front 13

photoperiodism

Back 13

occurrence of plant processes,such as germination and flowering,according to the time of year

Front 14

phototropin

Back 14

blue-light receptor that promotes phototropism, stomatal opening and closing, and other responses that promote photosynthesis

Front 15

phototropism

Back 15

directional bending of a plant toward a light source

Front 16

phyllotaxy

Back 16

arrangement of leaves on a stem

Front 17

phytochrome

Back 17

plant pigment protein that exists in two reversible forms (Pr and Pfr) and mediates morphologic changes in response to red light

Front 18

pinnately compound leaf

Back 18

leaf type with a divided leaf blade consisting of leaflets arranged on both sides of the midrib

Front 19

pith

Back 19

ground tissue found towards the interior of the vascular tissue in a stem or root

Front 20

positive gravitropism

Back 20

growth toward Earth’s gravitational center

Front 21

primary growth

Back 21

growth resulting in an increase in length of the stem and the root; caused by cell division in the shoot or root apical meristem

Front 22

rhizome

Back 22

modified underground stem that grows horizontally to the soil surface and has nodes and internodes

Front 23

root cap

Back 23

protective cells covering the tip of the growing root

Front 24

root hair

Back 24

hair-like structure that is an extension of epidermal cells; increases the root surface area and aids in absorption of water and minerals

Front 25

root system

Back 25

belowground portion of the plant that supports the plant and absorbs water and minerals

Front 26

runner

Back 26

stolon that runs above the ground and produces new clone plants at nodes

Front 27

sclerenchyma cell

Back 27

plant cell that has thick secondary walls and provides structural support; usually dead at maturity

Front 28

secondary growth

Back 28

growth resulting in an increase in thickness or girth; caused by the lateral meristem and cork cambium

Front 29

sessile

Back 29

leaf without a petiole that is attached directly to the plant stem

Front 30

shoot system

Back 30

aboveground portion of the plant; consists of non-reproductive plant parts, such as leaves and stems, and reproductive parts, such as flowers and fruits

Front 31

sieve-tube cell

Back 31

phloem cell arranged end to end to form a sieve tube that transports organic substances such as sugars and amino acids

Front 32

simple leaf

Back 32

leaf type in which the lamina is completely undivided or merely lobed

Front 33

sink

Back 33

growing parts of a plant, such as roots and young leaves, which require photosynthate

Front 34

source

Back 34

organ that produces photosynthate for a plant

Front 35

statolith

Back 35

plant organelle that contains heavy starch granules; also known as amyloplast

Front 36

stele

Back 36

inner portion of the root containing the vascular tissue; surrounded by the endodermis

Front 37

stipule

Back 37

small green structure found on either side of the leaf stalk or petiole

Front 38

stolon

Back 38

modified stem that runs parallel to the ground and can give rise to new plants at the nodes

Front 39

strigolactone

Back 39

hormone that promotes seed germination in some species and inhibits lateral apical development in the absence of auxins

Front 40

tap root system

Back 40

type of root system with a main root that grows vertically with few lateral roots; found in dicots

Front 41

tendril

Back 41

modified stem consisting of slender, twining strands used for support or climbing

Front 42

thigmonastic

Back 42

directional growth of a plant independent of the direction in which contact is applied

Front 43

thorn

Back 43

modified stem branch appearing as a sharp outgrowth that protects the plant

Front 44

tracheid

Back 44

xylem cell with thick secondary walls that helps transport water

Front 45

translocation

Back 45

mass transport of photosynthates from source to sink in vascular plants

Front 46

transpiration

Back 46

loss of water vapor to the atmosphere through stomata

Front 47

trichome

Back 47

hair-like structure on the epidermal surface

Front 48

tuber

Back 48

modified underground stem adapted for starch storage; has many adventitious buds

Front 49

vascular bundle

Back 49

strands of stem tissue made up of xylem and phloem

Front 50

vascular stele

Back 50

strands of root tissue made up of xylem and phloem

Front 51

vascular tissue

Back 51

tissue made up of xylem and phloem that transports food and water throughout the plant

Front 52

venation

Back 52

pattern of veins in a leaf; may be parallel (as in monocots), reticulate (as in dicots), or dichotomous (as in Gingko biloba)

Front 53

vessel element

Back 53

xylem cell that is shorter than a tracheid and has thinner walls

Front 54

water potential

Back 54

the potential energy of a water solution per unit volume in relation to pure water at atmospheric pressure and ambient temperature; symbol Ψw

Front 55

whorled

Back 55

pattern of leaf arrangement in which three or more leaves are connected at a node

Front 56

cuticle

Back 56

waxy protective layer on the leaf surface

Front 57

thigmotropism

Back 57

directional growth of a plant in response to constant contact

Front 58

thigmomorphogenesis

Back 58

developmental response to touch

Front 59

abscisic acid

Back 59

plant hormone that induces dormancy in seeds and other organs; also known as ABA

Front 60

abscission

Back 60

physiological process that leads to the fall of a plant organ (such as leaf or petal drop)

Front 61

adventitious root

Back 61

aboveground root that arises from a plant part other than the radicle of the plant embryo

Front 62

apical bud

Back 62

bud formed at the tip of the shoot

Front 63

apical meristem

Back 63

meristematic tissue located at the tips of stems and roots; enables a plant to extend in length

Front 64

auxin

Back 64

plant hormone that influences cell elongation (in phototropism), gravitropism, apical dominance and root growth

Front 65

axillary bud

Back 65

bud located in the axil: the stem area where the petiole connects to the stem

Front 66

bark

Back 66

tough, waterproof, outer epidermal layer of cork cells

Front 67

bulb

Back 67

modified underground stem that consists of a large bud surrounded by numerous leaf scales

Front 68

Casparian strip

Back 68

waxy coating that forces water to cross endodermal plasma membranes before entering the vascular cylinder, instead of moving between endodermal cells

Front 69

chromophore

Back 69

molecule that absorbs light

Front 70

collenchyma cell

Back 70

elongated plant cell with unevenly thickened walls; provides structural support to the stem and leaves

Front 71

companion cell

Back 71

phloem cell that is connected to sieve-tube cells; has large amounts of ribosomes and mitochondrion

Front 72

compound leaf

Back 72

leaf in which the leaf blade is subdivided to form leaflets, all attached to the midrib corm rounded, fleshy underground stem that contains stored food

Front 73

cortex

Back 73

ground tissue found between the vascular tissue and the epidermis in a stem or root

Front 74

cryptochrome

Back 74

protein that absorbs light in the blue and ultraviolet regions of the light spectrum cuticle waxy protective layer on the leaf surface

Front 75

cytokinin

Back 75

plant hormone that promotes cell division

Front 76

dermal tissue

Back 76

protective plant tissue covering the outermost part of the plant; controls gas exchange

Front 77

endodermis

Back 77

layer of cells in the root that forms a selective barrier between the ground tissue and the vascular tissue, allowing water and minerals to enter the root while excluding toxins and pathogens

Front 78

epidermis

Back 78

single layer of cells found in plant dermal tissue; covers and protects underlying tissue

Front 79

ethylene

Back 79

volatile plant hormone that is associated with fruit ripening, flower wilting, and leaf fall

Front 80

fibrous root system

Back 80

type of root system in which the roots arise from the base of the stem in a cluster, forming a dense network of roots; found in monocots

Front 81

gibberellin

Back 81

plant hormone that stimulates shoot elongation, seed germination, and the maturation and dropping of fruit and flowers; also known as GA

Front 82

ground tissue

Back 82

plant tissue involved in photosynthesis; provides support, and stores water and sugars

Front 83

guard cells

Back 83

paired cells on either side of a stoma that control stomatal opening and thereby regulate the movement of gases and water vapor

Front 84

intercalary meristem

Back 84

meristematic tissue located at nodes and the bases of leaf blades; found only in monocots

Front 85

internode

Back 85

region between nodes on the stem

Front 86

jasmonates

Back 86

small family of compounds derived from the fatty acid linoleic acid

Front 87

lamina

Back 87

leaf blade

Front 88

lateral meristem

Back 88

meristematic tissue that enables a plant to increase in thickness or girth

Front 89

lenticel

Back 89

opening on the surface of mature woody stems that facilitates gas exchange

Front 90

megapascal

Back 90

pressure units that measure water potential; also known as MPa