Morphoanatomy of Root

Question 1

usually an underground part of the
plant

Answer 1

root

Question 2

The root with its branches is known

Answer 2

root system

Question 3

Functions of the roots

Answer 3

(1) anchoring the plant firmly to a substrate,
* (2) absorbing water and minerals,
* (3) producing hormones

Question 4

types of root systems

Answer 4

tap root system
fibrous root system

Question 5

develops from the embryonic root in the seed

Answer 5

Tap root system

Question 6

The roots are adventitious and
develop from stem tissue

Answer 6

fibrous root system

Question 7

has a main root that grows down vertically, and from which many smaller lateral roots arise

Answer 7

tap root system

Question 8

Most ___ have a single prominent ___ that is much larger than all the rest and numerous small ___ ___ or ___ ___ coming out of it

Answer 8

dicot ; taproot ; lateral roots ; branch roots

Question 9

has several to many roots of the same size that develop from the end of the stem, with smaller lateral roots branching off these roots

Answer 9

fibrous root system

Question 10

form in plants in which the embryonic root is short-lived.

Answer 10

fibrous root system

Question 11

The roots originate initially from the base of the embryonic root and
later from stem tissue.

Answer 11

fibrous root system

Question 12

do not arise from preexisting roots but from the stem, they are called adventitious

Answer 12

fibrous roots

Question 13

fibrous roots do not arise from
preexisting roots but from the stem, they are called

Answer 13

adventitious

Question 14

located closer to the soil surface, and forms a dense network of roots
that also helps prevent soil erosion

Answer 14

fibrous root system

Question 15

increase the absorptive and transport capacities of the root system

Answer 15

adventitious roots

Question 16

often extend down into the
soil to obtain water deep underground

Answer 16

tap root system

Question 17

relatively close to the ground surface, are adapted to obtain
rainwater from a larger area as it drains into the soil

Answer 17

fibrous root system

Question 18

The tip of a root is covered
by a thimble-like structure

Answer 18

root cap

Question 19

protects the delicate apical meristem as the root pushes through the abrasive soil during
primary growth

Answer 19

root cap

Question 20

secretes a polysaccharide slime
called mucigel that lubricates the soil around the tip of the root

Answer 20

root cap

Question 21

lubricates the soil around the tip of the root

Answer 21

mucigel

Question 22

what are the zones of cells at successive stages of primary growth

Answer 22

zone of cell division
zone of elongation
zone of maturation/differentiation

Question 23

is closest to the root tip; it is made up of the actively dividing cells of
the root meristem

Answer 23

zone of cell division

Question 24

includes the root apical meristem and its derivatives

Answer 24

zone of cell division

Question 25

New root cells are produced in this region, including the root cap.

Answer 25

zone of cell division

Question 26

A group of cells between the root cap meristem and the zone of cell division (meristem) of the root is called

Answer 26

quiescent center

Question 27

The cells in this region are also meristematic, but divide very slowly

Answer 27

quiescent center

Question 28

can provide new cells for both the root and the root cap meristems as needed

Answer 28

quiescent center

Question 29

the cell division zone of roots is usually only about

Answer 29

1 mm

Question 30

Typically, about a millimeter behind the tip of the root

Answer 30

zone of elongation

Question 31

pushes the tip farther into the soil

Answer 31

zone of elongation

Question 32

keeps adding cells to the younger end of the zone of elongation

Answer 32

root apical meristem

Question 33

cells complete their differentiation and become distinct cell types

Answer 33

zone of differentiation

Question 34

a region in which many of the epidermal cells extend out as narrow trichomes

Answer 34

root hair zone

Question 35

short-lived tubular extensions of epidermal cells located just behind the growing tip

Answer 35

root hairs

Question 36

can form only in a part of the root that is not elongating or they would be shorn off

Answer 36

root hairs

Question 37

greatly increase the root's surface area

Answer 37

root hairs

Question 38

A single layer of protective tissue covers its roots

Answer 38

epidermis

Question 39

composed primarily of loosely arranged parenchyma

Answer 39

cortex in eudicot root

Question 40

The outermost layer of the stele is a single layer of cells, which is just inside the endodermis

Answer 40

pericycle

Question 41

composed of parenchyma cells that remain meristematic, gives rise to lateral roots

Answer 41

pericycle

Question 42

the phloem and xylem are in separate alternating strands that in cross section are arranged in a circle, which consists of parenchyma cells

Answer 42

pith

Question 43

absorb most of the water that goes into plants

Answer 43

roots

Question 44

thin-walled slender extensions of root epidermal cells that greatly increase the surface area for absorption

Answer 44

root hairs

Question 45

Plants absorb water and dissolved minerals from the soil with the help of

Answer 45

root hairs

Question 46

Water moves into the roots by

Answer 46

osmosis

Question 47

The rate of water uptake is regulated by specialised water channels called

Answer 47

aquaporins

Question 48

The inner layer of the cortex controls the amounts and kinds of water and dissolved materials that enter the xylem in the root’s center.

Answer 48

endodermis

Question 49

Endodermal cells fit snugly against one another, and each cell has a special bandlike region, called

Answer 49

casparian strip

Question 50

Casparian strips contain ____, a fatty material that is waterproof.

Answer 50

suberin

Question 51

the continuous system of cell walls and intercellular air spaces in plant tissues.

Answer 51

apoplast

Question 52

Water moves exclusively through the cell wall without crossing any membranes.

Answer 52

apoplastic pathway

Question 53

is obstructed by the Casparian strip

Answer 53

apoplastic pathway

Question 54

consists of the entire network of cell cytoplasm interconnected by plasmodesmata

Answer 54

symplast

Question 55

Water travels from one cell to the next via the plasmodesmata

Answer 55

symplastic pathway

Question 56

primarily function to store starch and water underground as reserves for perennial species

Answer 56

storage roots

Question 57

examples of storage roots

Answer 57

carrots, sweet potatoes, turnips

Question 58

are capable of extensive growth through the air

Answer 58

prop roots

Question 59

examples of prop roots

Answer 59

banyan tree

Question 60

adventitious roots that grow from lower stem nodes.

Answer 60

stilt roots

Question 61

provide anchorage to the tree or plant to stand strong in the ground.

Answer 61

stilt roots

Question 62

living attached to the branches of trees

Answer 62

epiphytic aerial roots

Question 63

Their roots spread along the surface of the bark and often dangle freely in the air.

Answer 63

epiphytic aerial roots

Question 64

The snake·like roots gradually wrap around the host tree

Answer 64

strangling aerial roots

Question 65

shallow and concentrated near the surface

Answer 65

buttress roots

Question 66

some roots grow upward until they are above the high-tide level

Answer 66

pneumatophores/breathing roots

Question 67

may assist in getting oxygen to the submerged roots

Answer 67

pneumatophores

Question 68

thickened specialized root which is designed to shrink vertically under conditions of seasonal drought

Answer 68

contractile roots

Question 69

arise from nodes and helps the plant in climbing

Answer 69

climbing roots

Question 70

arise from leaf

Answer 70

foliar roots / Epiphyllous roots

Question 71

roots enter in the stem of host plant to absorbed nutrition from host

Answer 71

parasitic roots

Question 72

become green and synthesize food

Answer 72

assimilatory roots

Question 73

The roots of most species of seed plants (at least 80%) have a symbiotic relationship with soil fungi in which both organisms benefit.

Answer 73

mycorrhizae

Question 74

fungal hyphae penetrate between the outermost root cortex cells but never invade the cells themselves

Answer 74

ectomycorrhizal relationship

Question 75

fungi with slender, threadlike cells

Answer 75

hyphae

Question 76

hyphae penetrate the root cortex as far as the endodermis

Answer 76

endomycorrihizal association

Question 77

what type of plant does endomycorrhizal association occurs?

Answer 77

herbaceous plant

Question 78

allow plants to draw more nutrients and water from the soil

Answer 78

mycorrhizal fungi

Question 79

They also increase plant tolerance to different environmental stresses.

Answer 79

mycorrhizal fungi

Question 80

these fungi play a major role in soil aggregation process and stimulate microbial activity

Answer 80

mycorrhizal fungi

Question 81

In a small number of plants, especially legumes, a symbiotic relationship has evolved with nitrogen-fixing bacteria of the genus

Answer 81

rhizobium

Question 82

The nodules on plant roots contain bacteria capable of absorbing atmospheric nitrogen and converting it to ammonia, which the plant can use to make amino acids

Answer 82

rhizobium/ rhizobial bacteria

Question 83

produce multiple beneficial effects on plant growth stimulation, host defense against disease and survival under stress

Answer 83

rhizobia

Question 84

These chemicals tell every other living thing in the root zone how the plant is doing.

Answer 84

root exudates