Polllllllinationnnnn Flashcards
Pollination = , both gametes are
Autogamy /
Requirement ,,
Continued ____ pollination results in
Transfer of pollen grains from anther to stigma , non motile
Self pollination = pollen grains are transferred from anther to stigma of same floral
Synchrony in pollen grain & stigma , anther and stigma should lie close to each other
Self in inbreeding depression
Autonomy ways
Geitonogamy
Considered as self pollination, cross pollination
Xenogamy / /
Monocliny , cleistogamy , homogamy
When pollination takes place in b/w two flowers of same plant
Genetical point of view ( flowers are genetically identical ) , functionally or ecologically
Xenogamy , cross pollination, allogamy = transfer of pollen grains from anther to stigma of different plant
Xenogamy only type of pollination
Monoecious plant , flowers are , ☠️,
Eg
Dioecious plant , flowers , 💀,
In which genetically different types of pollen reaches to stigma
Both male and female +nt on same plant , Unisexual , prevents autogamy but not geitonogamy , castor , cucurbits ,coconut , maize p
Male and female are present on different plants , Unisexual, prevents both autogamy and geitonogamy
Adaptation of self pollination
Bisexuality / eg
Homogamy , increase ,eg
Cleistogamy
Eg
Monocliny / hermapheodite , pea
When both sex organ of flower mature at same time ,chances of self pollination , pea
Some plants bisexual flowers are formed which never open throughout life
Commelina , viola ( common pansy ) , oxalis , Fabaceae family
Cleistogamy flower 2 types
1 type of flower produce, even in
1 type of flower anther and stigma
Thus are
Cleistogamy is
Cleistogamous , chasmogamous flower = similar to flowers of other species with exposed anther & stigma
Assured seed set , absence of pollinators
Lie close to each other.
Invariably autogamous as there is no chance of cross pollination on stigma
Advantageous as well as disadvantage
Bud pollination eg
Adaptation of cross pollination /
Pollination occurs in bud stage before opening of flowers , wheat ,rice
Out breeding process
Unisexuality
Dichogamy
Chasmogamy
Heterostyly
Self sterility / self incompatibility
Unisexuality eg
Dichogamy , common
eg (notes
Types
Chasmogamy / , have
Date palm , papaya ( carica)
Pollen grain and stigma release are not synchronised , protandry ,
salvia,ficus,rosacea,
Protandry = pollens are released first ,
Protogyny = stigma becomes receptive
Anthesis = blooming of floral bud in flower , exposed anthers and stigma
Heterostyly =
Eg
Self incompatibility/ , is a
Prevents
Eg
Anther and stigma are placed in different positions so that the pollen can not come in contact with stigma of same flower , Primula , primrose , oxalis
Self sterility , genetic mechanisms
Self pollens from fertilising the ovules by inhibiting pollen germination/ pollen tube growth in pistil
Eg tabacco, apple, wits , pentunia
Prepotency
Agents of pollination types subtype
Growth of pollen tube of self pollination is low
Abiotic = by wind ( anemophily ) , by water ( hydrophiliy )
Biotic by insects ( entomophily
By birds ( ornithophily
By bats ( chiropterophily
By ants and termites ( myrmecophily
By snail ( malacophily
By snake ( ophiophily
Abiotic plants () are not
Anemophily , produce
Pollen grains are. Stigma is
Stamens are how , sexuality , pollen grains loss, direction
Wind and water pollinated flowers are not very colourful, do not produce nectar
Pollination by wind , enormous amount of pollen grains
Very small , light weight, dry ( non sticky) , Large , hairy , feathery , mucilagenous (sticky
Possess well exposed stamen , Unisexual , maximum, non directional process
Wind pollinated flowers ovule , flowers eg
_______ in styles and stigma which
Common in , eg
Single in each ovary , numerous in inflorescence , corn cob.
Tassels , wave in wind to trap pollen grain
Grasses , maize,sugarcane,bamboo,coconut,cannabis,date palm, gymnosperm, water hyacinth/eichornia , water lily
Hydrophily , number
Types
Epihydrophily eg
Eg plant sexuality , flowers are , pedicel (),
Pollination by water , 30 genera mostly monocots
Epihydrophily, hypohydrophily
Pollination takes place on surface of water vallisneria
Dioecious,Unisexual , stalk of female are long and coiled
Vallisneria pollen grains are released (activity ) , carried What activities doesn’t takes place in water
Hypohydrophily eg
Fresh water , marine water
In most water pollinated species, pollen grains are protected
Released on surface of water due to bursting of inflorescence of male plant , passively by water currents , pollination
Pollination takes place inside the water , zostera ( sea grasses), hydrilla
Vallisneria, hydrilla Zostera
From wetting by a mucilaginous covering
Seagrass (), female flowers , _____ pollen grain , carried
Zoophily , comman pollinating agents
Dominant biotic pollinating agent
Larger animals such as ,
Plants are ,,,, specifically adapted for
Zostera , remain submerged in water ,long ribbon are released in water , passively
Pollination by animals , bees , butterflies,bettles ,wasps , ants , moths , birds , bats
Insects particularly beeeeess
Primates ( lemurs ),arboreal ( tree - dwelling) rodents , reptiles ( gecko lizards and garden lizard )
Large , attractive, nectar , glands , particular species of animal
Entomophily , honey bees no
Insect pollinated flower , When flower are small then
Night flowering flower are pollinated by , are , flower colour
Flower pollinated by flies and beetles
Pollination by insects , 80% of insect pollination
Large, colourful , fragent , rich in nectar. A no of flower clusters in inflorescence to make them conspicuous
Moths , highly scented , white
Secrete foul odour to attract these animals
The pollen grains of insect pollinated are sticky due, Plants are
Eg
Yucca pollinated by
Due to pollen kit , ornamental plants
Lemon , coriander, onion , Lobia , apple , pear , compositeace family , salvia ( labia tea family ) , cucumber , cotton , tabacco , Brassica, eucalyptus
Pronuba yuccasela moth ( tegeticula moth )
Tallest flower ()pollinated by
Ficus
Hydrophytes
Ornithophilly eg
Chiropterophilly eg
Amorphophallus ( 6 feet) , same as yucca also provided space (safe ) for laying eggs
Fig occurs by blastophaga wasp (insect)
Nymphaea ( water lily ) , water hyacinth , nelumbo or nelumbium ( lotus )
By birds , callistemon ( bottle brush ) , bombax
By bats , anthacephalus kadamba , adasonia
Mango , papaya pollination
Rose is ()
Banana
Malacophilly / eg
Ophiophilly
By wind or insects (mainly by insects
By insects ( red/orange by birds )
By bats or birds mainly by birds
Malmacophilly eg snail ( crysthamum )
By snake eg Chandan scentum
Floral rewards ,,()
Lever mechanism/ eg
Orchid by
Rafflesia (),
Piston mechanism
Nectar , pollen grains , ( providing safe place to lay eggs eg yucca , amorphophallus )
Turn pipe mech , eg salvia
Ophyrus
( largest , foul odour ) , by carrion flies
Centuriea plant
Fertilization , discovered by in
Step 1 =
Step 2
They (who??) absorb what from where
Intine
Fusion of male gamete with female gamete , Strasburger (1884) in monotrappa plant
Pollen postal interaction = chemical dialogue which is acceptance/ rejection
Germination of pollen grain.
Pollen grain moisture and sugar contents from stigma and swell up
Of pollen grain grows out through the any germ pore of exine in form of pollen tube
Pollen develops from (cell), produces
More than one pollen tube = eg
Pollen tube arrangement
Male gamete formation by , how , essential elements , temperature growth, movement
Tube cell , enzymes which digest tissue of stigma and solid style
Polysiphonous = Malvaceae/ cucurbitaceae
1st generative cell and then vegetative nucleus
By generative cell by mitosis , boron and ca2+ , 20-30 c , apical , chemotropic
Entry of pollen tube into ovules , who guide
3 paths 1 = eg
2 = eg
3 = a)eg
b) eg
Obturators towards micropyle
Porogamy = pollen tube entry in ovule through micropyle ,most of Angiospermae
Chalozogamy = through chalazal end eg walnuts (juglaans )
Mesogamy = through intugments eg curcurbita
= through funicles eg pistaceae
P.t entry into embryo sac only through , synergids secrete , movement
2 synergids then , helped by , when vegetative nucleus degenerate
Then what happensss (process)
Whole contain (???) , goes where
Egg apparatus , chemicals , chematropic
1 die , by filliform apparatus , when tip of pollen tube entry into embryo sac
Tip bursts and swell ( endo osmosis)
Both male gamete inside synergids (further degenerate) , in central cell
X bodies
Both pollen nuclei fuse (when ) to form
Syngamy / =
Triple fusion forms =
Two dark granules appear in region of degenerating synergids
Diploid nucleus = secondary/ definitive nucleus (before/after entry of p.t into embryo sac
True mechanism of fertilisation = 1 male gamete with 1 egg cell to form diploid zygote
Primary endosperm nuclei = 2 male gamete with sec nuclei
Double fertilisation discovered by , nucleus no
Gametes no
What degenerates
Siphonogamy
Polyspermy /
Nawaschian in lilium plant , fritillaria , 5 (2polar nuclei ,1 egg , 2 male gamete
3(2 male gamete , 1 female gamete
All remaking cell of embryo sac like antipodal , synergids
Fertilization in which non motile gametes are carried through pollen tube
Supernumerary = entry of more than 1 pollen tube in ovules
Endosperm develops from, utilised by,fn ,Food stored in form of
Endosperm type
1st type food in , develop by , result in
No of free nuclei formed before cellularisation
Eg , common in
PEN after fertilisation , developing embryo , seed germination , starch
Nuclear , cellular,Helobial
Dicot plant ( polypetalous) , free nuclear division of pen , Multinucleated endosperm
Varies greatly ,
Coconut water of tender coconut ( 1000s of nuclei) (liquid syncytium ), in Angiospermae
Cellular endosperm found in , each division in pen is followed by
So ( endosperm remains ) , eg
Helobial endosperm , found in , type
First division followed by ( which side big )
Gamopetalous group , cytokinesis
Endosperm remain cellular from beginning , edible portion ( white kernel)
Monocot , intermediate
Two Unequal cytokinesis so 2 unequal size cell formed ( micropyle end side»_space; chalazal
Young endosperm rich in , From maize endosperm (hormone
The reserve food of endosperm is utilised till
Aleurone layer ( in ____ most layer of _____ have )
Rich in
During seed germination reserve food digested by
Auxin , geberellin , cytokinin Zeatin , auxin B
Development of photosynthetic tissue
In cereals one or few outer most layer of endosperm have thick wall and nonvaculated
Protein,spherosome , glycoxyisome
Hydrolytic enzyme like protase , amylase secreted by amylase
Endosperm absent in
Exception in endosperm Ploidy
Mosaic endosperm (eg)
Development of embryo in dicot plant first discovered in , by
Zygote undergoes , till , and then it
Some Angiospermae eg orchidaceae ( orchid) , trapa (trapaceae family )
Oenothera plant = diploid
Patches of different colours ( maize , tomato
Capsella , Hanstein
Resting phase , till development of endosperm , absorb food increase in size and forms oospore
Dicot plant. First division in oospore is , cells position,name
B divides , A ,structure
Quadrant stage
Suspenser
Fn
Transverse , towards micropyle = basal cell / suspended cell , towards chalazal end = apical cell/ terminal cell / embryonal cell
Transversals , vertically , T shape structure
Embryonal cell forms 4 embryonal cell
6-10 long filament
Push developing embryo towards food laden endosperm
Dicot Haustorial cell , hypophysis , stage
hypophysis type Fn
Proembryo , shape
—— position called
Micropyler suspenser cell swell up , suspenser cell near embryonal , octant
Hypobasal ( 4 cell near embryo ) raise to radical , hypocotyls ,
epi basal ( 4 cell towards chalazal , raise to plumule , two cotyledons
16 cell globular embryo , heart / cardiac
Curved called torpedo / chordate stage
Tropeda / , development known as
Meroblastic
Parthnocarpy senseless in ,eg
Chordate , cruciferae / ( dicot )
Embryo is formed suspenser dries and degenerate
( edible part is seed / endosperm , pomegranate (punica granatum) Wheats coconut
Development of embryo in monocot found in (first) , all division are , which cell do not divide further and only
____ cell divide transversally to form ( their position)
Which cell divide further and forms
Lilium , transverse , basal cell ( micropyle) , only increase in size (vasicular suspenser
Embrynical cell ( chalazal ) = cotyledon ( terminal ) , embryonal axis cell ( middle position)
Transverse in embryonal axis cell form plumule initial and radical initial
Monocot both the initial are
Who divides to form cotyledon
Plumule / radical covered by
In Angiospermae development of embryo is
Responsible to form embryo in lateral position
Apical cotyledon ( scutellum / Shield shape )
Cap like hard protective covering called coleoptile , coleorhiza
Meroblastic and endosporic ( towards chalazal
Polyembrony first time observed by ,in , common in
In Angiospermae eg
Cause of polyembryony
All 3 found in
Leeuwenhoek , citrus seed ( orange) , gymnosperm
Orange , lemon , nicotiona
Cleavage of zygote b budding
By fertilisation of synergids
And of antipodal cell
Lilium
Adventive embryony = (eg) ! ………… cell behave like zygote
From Nucellus eg
Eg of
Embryo of seed grow into
Types
Embryo is formed from any diploid cell ( cell of nucleus, integuments) of ovule , diploid
In citrus , mangifera indica , opuntia
Poly embrony
Sphorophyte plant
Epigel and hypogel germination
Epigel germination due to faster growth of , eg
Hypogel …………………… . Eg most of ,
Viviparous seed does not , o2 , found in eg
Hypocotyl cotyledons are pushed out of soil , papaya , cotton , turmeric , bean , mustard, castor
Epicotyl cotyledons are pushed out of soil , Monocot ,few dicot maize , rice , wheat , gram , pea , maongo
Imbibe water , low , muddy , saline condition , Mangroov , rhizophora
Viviparous no , germination occurs ( known as )
We can not
Seed generates , is basic unit of
___&____ of mature seed are crucial for storage of seed ,fn
Resting phase , inside the food while it is attach to parent plant ( insitu germination )
Preserve the seed for next session
New genetic combination leading to variation , agriculture
Dehydration & dormancy , be used throughout year and also rise crop in next season
Period of viability
Oldest eg , excavated from, _____ years of dormancy
Date palm () _____ years of dormancy, near
Orchid seed no , other ____ families like
Tiny seed large tree eg
Lotus viable for
In Angiospermae varies
Lupine (lupinus arcticus ) , arctic tundra , 10,000
( phoenix dactylifera ) , 2000, archeological excavation at King herod’s palace , Dead Sea
1000 of tiny sea , parasitic as Orobanche and striga
Ficus
1000 yaers
Water in dormancy period , through out life % , water absorbed through , o2 essential for
Favourable temperature
The embryo depends upon stored food () till
10-15% , 75-90,seed coat and micropyle ,oxidation process
20-25%
Endosperm, cotyledon , formation of primary root from radicle and first leaf from plumule
Photoblastic seed will eg
Apomixis form of , eg , offspring known as
Included in apomixis =
Diplospory / = eg
not germinate in dark , orchid , tobacco , lettuce
Asexual reproduction , eg asteraceae and grasses , clones ( Ramet )
Agnospermy= embryo formation does not involve meiosis and Syngamy
Diploid parthenogenesis Mmc directly gives rise to embryosac without meiosis (2n) eg asteraceae parthenium
Apospory eg
Parthenogenesis
Viability of seed can be found from ( chemical
Embryonal axis becomes (in that chemical
Formation of gametophyte directly from sporophyte (Nucellus or integuments) without meiosis eg hieracium ( asteraceae family
Formation of embryo from unfertilised egg
2,3,4triphenylterazholium (ttc)
Pink in colour in solution
Apogamy
What
Any haploid cell of female gametophyte (except egg cell ) forms haploid embryo withit fertilisation
