sexual reproduction in flowering plants

Question 1

several ____ and ____ changes takes place which leds to ____ and frther development of _____

Answer 1

hormonal, structural, differentiation, floral primodium

Question 2

inflorescences bear

Answer 2

floral buds and flowers

Question 3

stamen includes

Answer 3

anther and filament

Question 4

anther

Answer 4

terminal generally bilobed structure

Question 5

filament

Answer 5

long slender stalk

Question 6

proximal end of filament is attached to

Answer 6

thalamus or petal of flower

Question 7

number and length of stamens is

Answer 7

variable

Question 8

typical angiosperm anther is

Answer 8

bilobed

Question 9

each lobe has

Answer 9

two theca

Question 10

what divides the theca in the anther

Answer 10

a longitudinal groove, running lengthwise

Question 11

bilobed structure of an anther is distinct in

Answer 11

transverse section of anther

Question 12

anther

Answer 12

four sided tetragonal structure consisting of four microsporangia at corners two in each lobe

Question 13

microsporangia develop to form

Answer 13

pollen grains

Question 14

microsporangia extend

Answer 14

longitudinal through length of anther

Question 15

typical microsporangium is

Answer 15

circular in outline

Question 16

four walls of microsporangia

Answer 16

epidermis, endothecium, middle layers, tapetum and sporogenous tissue

Question 17

outer three layer functions of microsporangia

Answer 17

protection and dehiscence of anther

Question 18

tapetum layers

Answer 18

innermost layer , polyploid and multinucleated, dense cytoplasm

Question 19

functions of tapetum

Answer 19

forms sporopollenin, form callase enzyme, forms pollin kitt( protein + lipid ) , provide nutrition to pollen grains

Question 20

sporogenous tissue

Answer 20

when anther is young a group of compactly arranged homogenous cells occupy the centre of microsporangium called

Question 21

each cell of sporogenous tissue is capable of giving rise to

Answer 21

a microspore tetrad

Question 22

each cell of sporogenous tissue is a

Answer 22

potential pollen grain or pollen grain mother cell / microspore mother cells

Question 23

microsporogenesis

Answer 23

formation of pollen grain/ microspore from PMC from meiosis

Question 24

microspores dissociate from each other when

Answer 24

anther matures and dehydrates

Question 25

what represents male gametophytes

Answer 25

pollen grains

Question 26

pollen grains are generally

Answer 26

spherical

Question 27

size of pollen grains

Answer 27

25-50 micrometers in DIAMETER

Question 28

how many layers does pollen grain have

Answer 28

two prominent layers

Question 29

outer layer of pollen grain

Answer 29

exine made up of sporopollenin

Question 30

sporopollenin

Answer 30

most resistant organic material known, it can withstand high temperatures and strong acids and alkali, no enzyme degrades sporopollenin.

Question 31

prominent apertures in pollen grain exine

Answer 31

germ pore, sporopollenin is absent

Question 32

pollen grains are well preserved as fossils because of presence of

Answer 32

sporopollenin

Question 33

what layer of pollen grain exhibits a fascinating array of patterns and designs

Answer 33

exine

Question 34

inner wall of sporopollenin

Answer 34

intine

Question 35

intine of pollen grain

Answer 35

thin and continuous layer made up of cellulose and pectin

Question 36

outer most layer of pollen grain

Answer 36

plasma membrane

Question 38

mature pollen grains contain two cells

Answer 38

vegetative and generative cells

Question 39

vegetative cell of pollen grain

Answer 39

larger in size, abundant food reserve, large irregular nucleus

Question 40

generative cell of pollen grain

Answer 40

small, dense cytoplasm, spindle shaped, nucleus present

Question 41

generative cell floats in cytoplasm of

Answer 41

vegetative cells

Question 42

pollen grains mature and form two cells by which division

Answer 42

asymmetrical mitosis

Question 43

vegetative cells is also called

Answer 43

tube cells

Question 44

what percent of angiosperms shed at 2 celled stage

Answer 44

60%

Question 45

in 40 precent of angiosperms, what cells divides to form two male gametes ; stage is called

Answer 45

generative cells, symmetrical division ; 3 celled stage

Question 46

pollen allergy / hay fever causing plants

Answer 46

parthenium/carrot grass, anaranthus, chenopodium

Question 48

pollen grains are rich in

Answer 48

nutrients

Question 49

____ is used asfood supplements

Answer 49

pollen tablets

Question 50

pollen consumption

Answer 50

increases p performances of athletes and race horses

Question 51

the period for which pollen grains remain viable is

Answer 51

variable

Question 52

viabiliity of pollen grains depends on

Answer 52

prevailing temperature and humidity

Question 53

in cereals like

Answer 53

rice, wheat pollen grains lose viabiliity within 30 minutes

Question 54

pollev viability is for a period of months in members of

Answer 54

rosaceae, leguminoseae and solanaceae

Question 55

it is possible to store ppollen grains for years in

Answer 55

-196°C liquid nitrogen

Question 56

in dicots how many germ pores are present

Answer 56

3 germ pores - tricoplet condition

Question 57

in monocots how many germ pores are present

Answer 57

1 germ pores - monocopate condition

Question 58

each pistil has ___ parts

Answer 58

three

Question 59

stigma

Answer 59

serves as landing platform for pollen grains

Question 60

style

Answer 60

long slender stalk

Question 61

ovary

Answer 61

basal bulged part of ovary

Question 62

inside ovary is the

Answer 62

ovarian cavity ( locule )

Question 63

placenta is present in

Answer 63

ovarian cavity

Question 64

arising from the placenta are

Answer 64

megasporangia

Question 65

one ovule is found in

Answer 65

rice, wheat, mango

Question 66

many ovules are found in

Answer 66

watermelon, orchids, papaya

Question 67

ovule is attached to placenta by

Answer 67

funicle

Question 68

what is hilum

Answer 68

region where funicle fuses with ovule

Question 69

protctive layer of ovule

Answer 69

integuments

Question 70

integuments circle ; except

Answer 70

the nucellus ; except at the tip where a small opening called micropyle is present

Question 71

opposit to.micropyle

Answer 71

chalazal end ; represneting basal part of ovary

Question 72

nucellus

Answer 72

mass of cells ; abundant food reserve

Question 74

where is the embryo sac located

Answer 74

nucellus

Question 75

megasporogenesis

Answer 75

formation of megaspore from megaspore mother cells

Question 76

ovules dofferentiate from megaspore mother cell in

Answer 76

micropylar region

Question 77

megaspore mother cell

Answer 77

large cell containing dense cytoplasm snd prominent nucleus

Question 78

meiosis of mmc forms

Answer 78

4 megaspores

Question 79

embryo sac is also called

Answer 79

female gametophyte

Question 80

embryo sac formation from a single megaspore is called

Answer 80

monosporic development

Question 81

in majority angiosperms, functional megaspore

Answer 81

is one and the rest of the three degenerate

Question 82

nucleus of the functional microspore divides

Answer 82

mitotically to form teo nuclei which move to opposite poles, and then two. more times

Question 83

3 generational division in megaspore is

Answer 83

strictly free nuclear, no cell wall deposition

Question 84

cell wall are laid down after

Answer 84

8 nucleate stage

Question 85

cell wall is deposited, in how many out of eight

Answer 85

six

Question 86

polar nuclei are situated

Answer 86

below the egg apparatus in central cell

Question 87

antipodal cells

Answer 87

three cells grouped together in chalazal end

Question 89

egg aparatus

Answer 89

three cells grouped togther at micropylar end, egg cell, two synergeids

Question 90

synergeids

Answer 90

have cellular thickening at micropylar end called filliform aparatus which guide pollen tube to (synergeids) micropyle

Question 91

a typical angiosperm embryo sac at maturity has

Answer 91

8 nuceli, 7 cells

Question 92

pollination tra

Answer 92

transfer of pollen grains from anther to stigma

Question 93

autogamy

Answer 93

transfer of pollen grains from anther to stigma in the same flower in same plant

Question 94

conditions for autogamy

Answer 94

bisexual flower, homogamy, clistogamous flower, bud pollination

Question 95

bud pollination ; examples

Answer 95

when pollination occurr during bud stage ; rice pea

Question 96

clistogamous flower examples

Answer 96

oxalis, commelina, viola(common pansy )

Question 97

clistogamous are

Answer 97

invariably autogamous cuz no cross pollination can occur

Question 98

clistogamous fliwer produce

Answer 98

assured seed sets

Question 99

but due to bud pollination,

Answer 99

there is low genetic variation( inbreeding depression)

Question 100

geitonogamy

Answer 100

transfer of pollen grains from anther of one flower to stigma of another flower

Question 101

geitonogamy is

Answer 101

functionally cross pollination but genetically self pollination

Question 102

xenogamy/ cross pollination

Answer 102

transfer of pollen grains from anther to stigma of one flower to flower of different plant

Question 103

pollination where genetic variation occurrs

Answer 103

xenogamy