Chapter 35

Question 1

How are plants organized?

Answer 1

Plants have organs composed of different tissues,

which in turn are composed of different cell types

Question 2

A cell…

Answer 2

is the fundamental unit of life

Question 3

A tissue

Answer 3

is a group of cells consisting of one or more

cell types that together perform a specialized function

Question 4

An organ…

Answer 4

onsists of several types of tissues that

together carry out particular functions

Question 5

Basic Vascular Plant Organs:

Answer 5

Roots, stems, and leaves

Question 6

How are the three basic organs organized?

Answer 6

They are organized into a root system and a shoot

system

Question 7

Roots rely on…

Answer 7

sugar produced
by photosynthesis
in the shoot
system

Question 8

Shoots rely on…

Answer 8

water and 
minerals 
absorbed by the 
root system
Basic

Question 9

A root is an organ with important functions:

Answer 9

• Anchoring the plant
• Absorbing minerals and water
• Storing carbohydrates

Question 10

The primary root

branches to form

Answer 10

lateral roots for
anchorage and water
absorption occurs

Question 11

Tall plants with large shoot masses generally have

Answer 11

a taproot system

Question 12

The taproot generally develops from

Answer 12

the primary root

and functions in anchoring the plant in the soil

Question 13

Small or trailing plants generally have a

Answer 13

fibrous root system that spreads out like a thick

mat below the soil surface

Question 14

Root hairs…

Answer 14

are finger-like extensions of epidermal cells, form near the root tip and increase the absorptive surface of the root

Question 15

Most root systems form

Answer 15

mycorrhizal associations

Question 16

A stem is a plant organ

consisting of

Answer 16

an alternating system of nodes and internodes

Question 17

nodes..

Answer 17

the points of leaves attachment

Question 18

internodes…

Answer 18

the stem segments between nodes

Question 19

The growing shoot tip, or apical bud causes

Answer 19

elongation of a young shoot

Question 20

An axillary bud is a structure that

Answer 20

has the potential

to form a lateral branch, thorn, or flower

Question 21

The primary function of

the stem is to

Answer 21

elongate and orient the shoot to maximize

photosynthesis

Question 22

Many plants have
modified stems that
perform alternate
functions, for example…

Answer 22

rhizomes, stolons, tubers

Question 23

The leaf is the

Answer 23

main photosynthetic organ of most vascular plants

Question 24

Leaves functions:

Answer 24

intercept light, exchange gases, dissipate
heat, and defend the plant from herbivores and
pathogens

Question 25

Leaves generally consist of

Answer 25

a flattened blade and a stalk called the petiole

Question 26

a petiole...

Answer 26

which joins the leaf to a | node of the stem

Question 27

``` Some plant species have evolved modified leaves that serve various functions, for example... ```

Answer 27

spines, tendrils, storage leaves, and reproductive leaves

Question 28

Roots, stems, and leaves are composed of three tissue types:

Answer 28

dermal, vascular, and ground tissues

Question 29

In nonwoody plants, the dermal | tissue system consists

Answer 29

of a epidermis and a cuticle

Question 30

epidermis

Answer 30

covered in a waxy coating

Question 31

cuticle

Answer 31

that helps | prevent water loss

Question 32

In woody plants, protective tissues | called periderm

Answer 32

replace the epidermis in older regions of stems | and roots

Question 33

Tissues that are neither | dermal nor vascular are the

Answer 33

ground tissue system

Question 34

Ground tissue internal to the | vascular tissue

Answer 34

is pith

Question 35

ground tissue external to the vascular tissue

Answer 35

is cortex

Question 36

Ground tissue includes cells | specialized for

Answer 36

storage, photosynthesis, support, and | transport

Question 37

The two vascular tissues are

Answer 37

xylem and phloem

Question 38

Xylem

Answer 38

conducts water and dissolved minerals upward | from roots into the shoots

Question 39

Phloem

Answer 39

transports sugars from where they are made | (primarily leaves) to storage or growth sites

Question 40

The vascular tissue of a root or stem is collectively | called

Answer 40

the stele

Question 41

In angiosperms, the stele of the root is a

Answer 41

solid central vascular cylinder divided into vascular bundles, strands of xylem and phloem

Question 42

The two types of water-conducting cells

Answer 42

tracheids and vessel elements are dead and | lignified at maturity

Question 43

Cells of the phloem are

Answer 43

alive at maturity, but lack | organelles

Question 44

In seedless vascular plants and gymnosperms, sugars are

Answer 44

transported through sieve cells

Question 45

In angiosperms, sugars are

Answer 45

transported in sieve tubes, chains of cells called sieve-tube elements

Question 46

Sieve plates are

Answer 46

the porous end walls between sieve -tube elements that allow fluid to flow between cells along the sieve tube

Question 47

Each sieve-tube element is connected to a | companion cell by

Answer 47

plasmodesmata whose nucleus and ribosomes also serve the adjacent sieve-tube element

Question 48

indeterminate growth

Answer 48

A plant can grow throughout its life due to the activity of meristems, unspecialized tissues composed of dividing cells

Question 49

determinate growth

Answer 49

Most animals and some plant organs cease to grow at a certain size

Question 50

There are two main types of meristems:

Answer 50

apical meristems and lateral meristems

Question 51

Apical meristems

Answer 51

ocated at the tips of roots and | shoots, lengthens them; called primary growth

Question 52

Lateral meristems add

Answer 52

thickness to woody plants | secondary growth

Question 53

There are two lateral | meristems:

Answer 53

the vascular | cambium and the cork cambium

Question 54

The vascular cambium adds

Answer 54

layers of vascular tissue called secondary xylem (wood) and secondary phloem

Question 55

The cork cambium replaces

Answer 55

the epidermis with periderm, | which is thicker and tougher

Question 56

The root tip is covered by a root | cap, which

Answer 56

protects the root apical meristem as the root pushes through soil

Question 57

Growth occurs just behind the root | tip, in three zones of cells:

Answer 57

Zone of cell division Zone of elongation Zone of differentiation (maturation)

Question 58

The primary growth of roots | produces

Answer 58

the epidermis, ground | tissue, and vascular tissue

Question 59

In most eudicots, the xylem is

Answer 59

starlike in appearance with | phloem between the “arms”

Question 60

In many monocots, a core of ground tissue is

Answer 60

surrounded by alternating rings of xylem and phloem

Question 61

A shoot apical | meristem is a

Answer 61

dome-shaped mass of dividing cells at the | shoot tip

Question 62

The leaves of the | apical bud protect

Answer 62

the meristem

Question 63

Axillary buds | develop from

Answer 63

meristematic cells left at the bases of leaf primordia

Question 64

In most eudicots, the vascular tissue consists

Answer 64

of vascular | bundles arranged in a ring

Question 65

In most monocot stems, the vascular bundles are

Answer 65

scattered | throughout the ground tissue

Question 66

Leaves develop from

Answer 66

leaf primordia along the sides | of the shoot apical meristem

Question 67

stomata

Answer 67

pores that allow CO2 and O2 exchange between the air and the photosynthetic cells in a leaf

Question 68

Each stomatal pore is flanked

Answer 68

by two guard cells, which regulate the pore’s opening and closing and control water loss

Question 69

The ground tissue in a leaf, called mesophyll, is

Answer 69

between the upper and lower epidermis

Question 70

The mesophyll of eudicots has two layers:

Answer 70

palisade and spongy

Question 71

Veins are the leaf’s vascular bundles, function as

Answer 71

the leaf’s skeleton, and are protected by bundle sheaths

Question 72

Secondary growth, the growth in thickness produced by

Answer 72

lateral meristems

Question 73

Secondary growth occurs

Answer 73

in gymnosperms and many eudicots, but is rare in monocots

Question 74

Secondary growth occurs in

Answer 74

stems and roots of woody plants but rarely in leaves

Question 75

Primary growth and secondary growth occur

Answer 75

simultaneously

Question 76

In a woody stem, the vascular cambium is located

Answer 76

outside the pith and primary xylem and to the inside of the primary phloem and the cortex

Question 77

In a woody root, the vascular cambium forms

Answer 77

exterior to the primary xylem and interior to the primary phloem

Question 78

Secondary xylem accumulates as

Answer 78

wood and consists of tracheids, vessel elements (only in angiosperms), and fibers

Question 79

Early wood

Answer 79

formed in the spring in temperate regions, | has thin cell walls to maximize water delivery

Question 80

Late wood

Answer 80

formed in the summer, has thick-walled | cells and contributes more to stem support

Question 81

Thick rings

Answer 81

indicate a year with warm or wet growing conditions

Question 82

thin rings

Answer 82

indicate a | cold or dry year

Question 83

The outer layers, known as sapwood, still

Answer 83

transport materials through the xylem

Question 84

Older secondary phloem sloughs off as

Answer 84

part of the bark and does not accumulate