sexual reproduction in plants package Flashcards
(123 cards)
1
Q
two anther lobes are seperated by a deep groove infront and are attached to each other by
A
vascularized sterile tissue called connective
2
Q
the centre of a microsporangia consists of
A
homogenous meristematic cells called primary sporogenous cells
3
Q
epidermis of arceuthobium
A
develops fibrous thickening called exothecium
4
Q
alpha cellulosic fibrous bands are absent in
A
hydrophytes like hydrocharitaceae
5
Q
cells of middle layer are
A
ephemeral, 1-3 layered, degenerate at maturity
6
Q
tapetal cells show increase in
A
DNA content
7
Q
inside each microsporangium,
A
several thousands of microspores or pollen grain are formed
8
Q
cell wall of pollen grain is called
A
sporoderm
9
Q
why is exine made of sporopollenin
A
to protect the wall of the pollen grain against hazardous environment during pollination
10
Q
why is the array of patterns exhibited by exine layer of importance
A
they are of taxonomical significance
11
Q
pollination takes place at 2 celled stage in
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60% of angiosperms
12
Q
pollen grains are shed at 3 celled stage in
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40% of angiosperms
13
Q
apocarpous pistil
A
michelia
14
Q
syncarpous pistil
A
papaver
15
Q
ovary with single ovule
A
rice, wheat, mango
16
Q
ovary with many ovules
A
papaya, watermelon, orchids
17
Q
chalazal end represents
A
basal part of ovary
18
Q
nucellus
A
parenchymatous mass of cells which forms body of ovule
19
Q
depending development of nucellus there are two types of ovules
A
crassinucellate ovule, tenunicellulate ovule
20
Q
examples of crassinucellate ovule
A
polypetalate
21
Q
example of tenunicellulate ovule
A
gamopetale
22
Q
orthotropous ovule ; examples
A
where chalazal end, univle and micropyle are in same line ; piper, polygonum, cycas
23
Q
anatropos ovule
A
where ovule is at a 180 angle , inverted ovule, it is the most common ovule and found in 82% of angiosperm families
24
Q
when mmc undergoes meiosis which out of the four remain functional
A
one near the chalazal end remains functional and the rest three degenerate
25
who classification embryo sac on the basis of number of megaspore nuclei participating in embryo sac formation
p maheshwari
26
monosporic development example
polygonum, oenothera
27
bisporic development examples
allium, endymion
28
tetrasporic embryo sac examples
adoxa, plumbago
29
what percentage of flowering plants show polygonum
80%
30
polygonum development was studied by
strausburger
31
egg aparatus is present at
micropylar end
32
antipodal cells are present at
chalazal end
33
synergeids are also called
helper cells or cooperative celld
34
vacuole and nucleus in synergeids
micropylar nucleus and chalazal vacuole
35
cell wall of synergeids
lacks a cell wall at maturity on their chalazal side
36
the eggs apparatus shows cytoplasmic
polarity opposite to synergeids
37
cell wall os egg aparatus
thicker on micropylar end
38
vacuole and nucleus of egg aparatus
micropylar vacuole chalazal nucleus
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connection between egg and synergeids
plasmodesmata
40
largest cell of embyo sac
central cell
41
vegetative cells of embryo sac
antipodal cells
42
polar nuclei fuse before
fertilisation
43
conditions to ensure self pollination
bisexual flower, homogamous condition - mandatory, clistogamous
44
bud pollination examples
pea, rice
45
wind pollinated plants examples
grasses, maize, sugarcane, wheat, bamboo in 30 genera of monocots
46
hydrophily examples
vallisneria, hydrilla, zostera
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epihydrophily examples
vallisneria
48
hypohydrophily examples
zostera( sea grasses)
49
water plants pollinated by insects
water lily, water hyacinth
50
biotic agents as reptiles and primated
lemur in ravenala, lizard in flax
51
most common biotic agent
insects(entomophily)
52
symbiotic relationship in pollination by biotic agents
pronuba moth lays its eggs into yucca plant
53
nectar robbers
queen of bombus affinis perforates aquilegia spurs and steals nectar
54
55
monoecious plant prevents ; examples
it prevents autogamy; castor maize
56
dioecious plants prevent ; examples
autogamy as well as geitonogamy; vallisneria, papaya
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protandrous examples
sunflower, cotton
58
protgynous examples
ficus, aristolochia
59
epihydrophily is also found in
ape grass
60
pseudocopulation occurs in
ohyrus
61
ability of pitil to recognise the pollen is of a continuous
chemical dialogue between pollen and pistil
62
pollen grain produces pollen tube throught
germ pore
63
growth of pollen tube towards ovay is
chemotropic
64
if pollen grains are shed at 2 celled stage then generative cells divides during
growth of pollen tube towards ovary, right before fertilization
65
most common mode of entry of pollen tube into ovule
porogamy( micropyle)
66
chalazogamy; examples
chalazal end; casuarina
67
mesogamy; examplles
integuments; curcubita
68
what guides the entry of pollen tube
vegetative cells, filiform apparatus in synergids
69
pollen potil interaction is a __ process
dynamic
70
in vitro pollination examples
pea, chick pea, crotalaria, balsam, vinca
71
other male gamete moves towards
polar nuclei to fuse with them to form primary endosperm nucleus
72
what kinds of fertilization occurs in embryo sac
syngamy and triple fusion
73
endosperm is absent in families such as
orchidaceae,podostemaceae, trapaceae
74
Starchy endosperm is found in
cereals, rice wheat
75
proteinaceous endosperm
maize
76
oil endosperm
castor, coconut
77
cellulosic endosperm
ivory palm
78
hemi cellulosic endosperm
date palm
79
stony endosperm
betel nut(areca nut), phoenix dactylifera
80
diploid endosperm found in
oenothera
81
nuclear endosperm ; examples
pen undergoes nuclear division to give free nuclei and then wall formation begins to maje endosperm a multicellular tissue; cotton, maize
82
83
cellular endosperm ; examples
pen divides many times to form nuclei and wall consecutively ; petunia
84
helobial
coconut water is free nucleat endosperm and surrounding white kernel is cellular
85
ex albuminous seeds
pea, beans, groudnut
86
albuminous seeds
castor, coconut, rice, wheat, maize, barley
87
zygote(oospore) divides
unequally and forms an embryonic cell towards the chalaza and a large suspensor cell towards micropyle
88
suspensor cell undergoes
transverse divisions to form 6-10 cells long suspensor
89
first cell of suspensor
called haustorium or vesicular cell towards micropyle and
90
last cell of suspensor
towards chalaza called as hypophysis
91
what does hypophysis form
radicle tip
92
the embryonal cell divides
once transverse and twice vertically to form 8 celled two tiered embryo
93
epibasal tier forms
two cotelydons and plumule
94
hypobasal forms
hypocotly and most of the radicle
95
octant embryo undergoes perclinal divisions to form
protoderm, procambium, ground meristem
96
embryo is initially
globular but later forms heart shaped and then normal
97
epicotly
portion of embryonal axis above the level of cotelydons
98
hypocotly
portion of embryonal axis below the cotelydons which forms radicle or root tip
99
embryonal cell in monocots
divides twice transverly once to form a suspensor and terminal cell and again to form a top and middle cell
100
the terminal cell in monocots divides again
vertically to form globular embryo
101
single cotlyden in monocots is called
scutellum
102
radicle and root cap are enclosed in
an undiffereiated tissue called coleorhiza
103
epicotly has
shoot apex and leaf primordia in a hollow foliar structure called coleoptile
104
remains of second cotlydon in monocots is called
epiblast
105
double fertilization was discovered by
nawaschin and guignard in lillium and fritillaria
106
most common endosperm in angiosperms is
nuclear
107
perispermic seed examples
remains of nucellus is seen ; black pepper, beet
108
function of micropyle after formation of seed
facilitates water and o2 entry
109
function of embryo
gives rise to mature plant and maintains continuity of generation
110
dormancy of seed
state of inactivity of seed where its not able to germinate, moistur content of seed decreases and reaches 10-15%
111
seeds viable for hundreds of years
lupinus arcticus, phoenix dactylifera (date palm)
112
fruits containing many seeds
orhids, parasitic plants like orobanche, striga
113
true fruit examples
mango, coconut, pomegranate
114
false fruit; examples
develops from other floral parts along with thalamus and development of ovary wall; apple, pear, cashewnut, strawberry
115
parthenocarpic fruits;examples
fruits developed without process of fertilization, seedless can be produced through applications of growth hormones like auxins ; banana, grapes
116
apomixis is seen in
asteraceae and grasses
117
apomixis
production of seeds without fertilization
118
adventive embryony; egs
sporophytic embryony where embryo is formed from nucellus or integument cells ; citrus, opuntia, mango
119
recurrent agamospermy
diploid embryo sac is formed from megaspore mother cell of nucellar cell ; apple, pear
120
who discovered polyembryony
leewenhoek in citrus
121
hybrid varieties examples
maize, tomato, cauliflower
122
disadvantage of hybrid varieties
they are not maintained and they segregate in 2nd genderation
123
advantage of apomixis
embryo develops from diploid cells, segregation of traits doesn't occur
