What is the role of gibberellins in parthenocarpy?
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Gibberellins can induce parthenocarpy artificially by promoting fruit development without fertilization, which can be achieved through methods like spraying gibberellins or delaying pollination.
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What is the role of gibberellins in parthenocarpy?
Gibberellins can induce parthenocarpy artificially by promoting fruit development without fertilization, which can be achieved through methods like spraying gibberellins or delaying pollination.
What is the testa?
The testa is the typical outer seed coat that protects the seed.
What is the second mitotic division concerned with?
The second mitotic division is concerned with the generative cell only and gives rise to two non-motile male gametes.
What are polar nuclei?
Polar nuclei are two nuclei that migrate towards the center of the embryo sac and are formed during the development of the female gametophyte.
What is Geitonogamy?
Geitonogamy is the transfer of pollen grain to a stigma of a different flower produced on the same plant. It is functionally similar to cross pollination but does not bring about genetic variations.
What is the female reproductive whorl of a flower called?
The female reproductive whorl of a flower is called the gynoecium (Pistil).
What is an apocarpous flower?
A flower with many free carpels is called apocarpous.
What is Dichogamy?
It is a mechanism in which anthers and stigmas mature at different times in a bisexual flower to prevent self-pollination.
What is recurrent apomixis?
Recurrent apomixis is a type of apomixis where the embryo sac arises from an archesporial cell or another part of the nucellus, often involving diplospory.
What is parthenocarpy?
Parthenocarpy is the condition in which fruit develops without fertilization, resulting in seedless fruits. It occurs naturally in some varieties of plants like Pineapple, Banana, and Papaya, often due to the production of auxin in the unfertilized ovary.
What is agamospermy?
Agamospermy is the process where seeds are produced without meiosis and syngamy, meaning the embryo develops without the typical fertilization process.
What are Antipodal cells?
Antipodal cells are a group of three cells present at the chalazal end of the embryo sac in angiosperms.
What is the cellular type of endosperm?
The cellular type of endosperm is formed when the division of the triploid primary endospermic nucleus is immediately followed by wall formation, resulting in a cellular structure from the beginning.
What is pollination?
Pollination is the transfer of pollen grains from the anther to the stigma of a flower, which is a prerequisite for fertilization.
What are adaptations in ornithophilous flowers?
Ornithophilous flowers are usually brightly colored, large, and showy; they secrete profuse, dilute nectar; pollen grains are sticky and spiny; and they are generally without fragrance due to birds' poor sense of smell.
What is the function of a flower?
The function of a flower is to produce haploid gametes and ensure that fertilization takes place.
What is Double Fertilization?
Double fertilization is a complex fertilization mechanism in flowering plants where one male gamete fuses with the egg to form a diploid zygote, while the second male gamete fuses with the diploid secondary nucleus to form the primary endosperm nucleus.
What is Anemophily?
Anemophily is pollination by wind, where plants like wheat, rice, and corn are primarily wind-pollinated.
What is mosaic endosperm?
Mosaic endosperm is a type of endosperm that contains tissues of two different types, often resulting in a patchy or mosaic pattern, as seen in plants like corn.
What is the significance of Double Fertilization in angiosperms?
Double fertilization ensures that the parent plant invests in a seed with a food store only if the egg is fertilized, thus optimizing resource allocation.
What is Spore Formation?
Spore formation is a method of asexual reproduction where organisms like Chlamydomonas produce flagellated, motile zoospores that can grow independently into new individuals.
What is perisperm?
Perisperm is a thin, papery layer that may persist in some genera, such as black pepper and beet, derived from the nucellus in the ovule.
What is Protandry?
It is a type of dichogamy where the androecium matures earlier than the gynoecium, preventing self-pollination.
What is polyembryony in Citrus seeds?
Polyembryony is the development of more than one embryo inside a seed, resulting in the emergence of multiple seedlings. It was first observed in the Citrus genus and can be classified as true or false depending on the origin of the embryos.
What is monosporic development?
Monosporic development is the method of embryo sac development from a single megaspore.
What are Clones?
Clones are morphologically and genetically identical individuals produced through asexual reproduction, inheriting the genes of the parent organism.
What is Homogamy?
Homogamy is when the anther and stigma of a flower mature at the same time, facilitating self-pollination.
What does the term Hypocotyl refer to?
The Hypocotyl is the part of the embryo that develops into the stem below the cotyledons.
What is the zygote in the context of seed formation?
The zygote is the fertilized egg that develops into the embryo after fertilization.
What is Herkogamy?
It is a mechanical device that prevents self-pollination by creating a natural physical barrier between the two sex organs in a bisexual flower.
Which of the following is the odd one out: Nucellus, Embryo sac, Micropyle, Pollen grain?
Pollen grain is the odd one out.
Why are pollination and seed formation crucial for fruit formation?
Pollination and seed formation are crucial because they initiate the development of fruits, which are essential for the reproduction of flowering plants.
What is Micropropagation?
Micropropagation is a method of carefully growing plants to produce many plantlets, often used in modern horticulture.
What is the significance of nucellar embryos?
Nucellar embryos are significant because they allow for the production of genetically uniform parental type seedlings, which can be beneficial in horticulture.
What are the four whorls of a typical flower?
The four different whorls of a typical flower are calyx, corolla, androecium, and gynoecium.
What is megasporogenesis?
Megasporogenesis is the process of formation of haploid megaspores from a diploid megaspore mother cell (MMC).
What is the tegmen?
The tegmen is the inner thin, membranous covering of the seed.
What are the three parts of a typical carpel?
The three parts of a typical carpel are the ovary, style, and stigma.
What are endospermic seeds?
Endospermic seeds, also known as albuminous seeds, are those in which the food reserves in the endosperm are partially used up during the development of the embryo, remaining conspicuous in the mature seed.
What is the funiculus in seed formation?
The funiculus is the stalk of the seed that connects the seed to the ovule before seed formation.
What are pollination syndromes?
Pollination syndromes are co-evolved physical characteristics of plants and pollinators that facilitate successful interactions for pollination.
What is the scutellum?
The scutellum is the single shield-shaped cotyledon found in monocot embryos, occupying the terminal position.
What is the function of the Endosperm during embryo development?
The Endosperm provides nourishment to the developing embryo and is consumed as the embryo matures.
What is coleorhiza?
Coleorhiza is the protective sheath that covers the radicle in monocot embryos.
What are the characteristics of insect pollinated flowers?
Insect pollinated flowers usually possess sticky pollens with a rough surface.
What is megasporogenesis?
Megasporogenesis is the process of formation of megaspores from the megaspore mother cell.
What parts of the pistil develop into fruits and seeds?
The ovary develops into fruits and the ovules develop into seeds.
What is the triploid endosperm?
The triploid endosperm is a nutritive tissue that develops from the triploid primary endosperm nucleus, which divides mitotically to provide nourishment to the developing embryo.
What is Xenogamy?
Xenogamy is a type of cross pollination where pollen grains from one flower are deposited on the stigma of a flower of a different plant belonging to the same species, generating genetically varied offspring.
What are the characteristics of pollen grains in hydrophilous flowers?
Pollen grains in hydrophilous flowers are long, unwettable due to mucilage, and have a specific gravity equal to that of water, allowing them to float.
What is apomixis?
Apomixis is the phenomenon of embryo formation through asexual reproduction without the formation of gametes or fertilization.
What is Autogamy?
Autogamy is a type of self-pollination where a bisexual flower is pollinated by its own pollen grains, resulting in genetically identical offspring.
What is embryogenesis?
Embryogenesis is the process of development of the zygote into an embryo, occurring at the micropylar end of the embryo sac.
What is a stamen?
An individual member of the androecium, consisting of a filament, connective, and anther.
What is a syncarpous flower?
A syncarpous flower is one that has many carpels fused together.
What is an anatropous ovule?
An anatropous ovule is a type of ovule in which the micropyle is directed downwards and is adjacent to the funiculus.
What is the significance of pollination contrivance?
Pollination contrivance refers to adaptations that plants develop to encourage specific pollinators, enhancing successful interactions between plants and their pollinators.
What is the role of the embryo sac?
The embryo sac is the female gametophyte, an oval, multicellular structure embedded in the nucellus.
What is Chalazogamy?
Chalazogamy is the entry of the pollen tube into the ovule through the chalaza.
What is the process of forming a two-celled proembryo?
The zygote divides to form a two-celled proembryo, consisting of a basal suspensor initial cell and a terminal embryonal initial cell.
What role do synergids play in Double Fertilization?
Synergids secrete chemicals that guide the growth of the pollen tube and facilitate the entry of male gametes into the embryo sac.
What is the role of sepals in flowers?
Sepals are green structures that protect the flower until it opens.
What is an embryo sac?
An embryo sac is a seven-celled and eight-nucleated structure formed during the development of the female gametophyte in angiosperms.
What are Abiotic Agents in pollination?
Abiotic agents are non-living agents that facilitate pollination, including wind and water.
What is Grafting?
Grafting is a method where parts of two plants are joined so that they grow as one plant, typically involving a scion and a stock.
What is the nuclear type of endosperm?
The nuclear type of endosperm is characterized by the primary endosperm nucleus dividing mitotically without wall formation, producing a large number of free nuclei.
What is non-recurrent apomixis?
Non-recurrent apomixis involves the usual meiotic division of the megaspore mother cell, forming a haploid embryo sac, with embryos arising from parthenogenesis or apogamy.
What does tetrasporongiate mean?
Refers to an anther that has four pollen sacs.
What is the function of the Radicle?
The Radicle is the part of the embryo that develops into the root.
What is sporopollenin?
A complex, non-biodegradable substance that makes up the thick outer layer (exine) of pollen grains.
What is the significance of the generative cell in pollen grain development?
The generative cell undergoes mitotic division to produce male gametes within the pollen grain.
What is the purpose of colored petals in flowers?
Colored petals attract insects that carry pollen, facilitating pollination.
Which type of pollination requires a pollinator but results in genetically similar offspring to autogamy?
Geitonogamy requires a pollinator but results in genetically similar offspring to autogamy.
How is endosperm formed in angiosperms?
Endosperm is formed by the fusion of polar nuclei and a male gamete.
What is seed viability?
Seed viability refers to the length of time seeds remain healthy and capable of germination under suitable conditions.
What is Budding in Yeast?
Budding is a common method of asexual reproduction in unicellular yeast, where one or more outgrowths (buds) are produced during favorable conditions, which then separate and develop into new individuals.
What is Hypohydrophily?
Hypohydrophily is a type of hydrophily where pollination occurs below the water surface, with pollen grains that are heavier than water sinking to reach the stigmas of female flowers.
What is chiropterophily?
Chiropterophily refers to pollination by bats, which can transport pollen over long distances, sometimes several kilometers.
What adaptations do hydrophilous flowers have?
Hydrophilous flowers are small, inconspicuous, have unwettable floral parts, and lack nectar and fragrance.
What is the structure of an anther?
An immature anther is made of parenchymatous tissue surrounded by a single-layered epidermis, generally dithecous and tetrasporongiate.
What is unisexuality in plants?
Unisexuality, also known as dioecism, is when a plant bears either male or female flowers, preventing self-pollination.
What is the function of the funiculus in an ovule?
The funiculus is a small stalk that attaches the ovule to the placenta.
What is Prepotency?
It is a phenomenon where pollen grains from other flowers germinate more rapidly on the stigma than pollen grains from the same flower.
What is the Hypophysis in the context of embryo development?
The Hypophysis is the lowermost cell of the suspensor that plays a role in the development of the root cap.
What is the role of the tapetum in the anther?
The tapetum is the innermost nutritive layer of the anther wall that encloses the sporogenous tissue.
Who discovered Double Fertilization?
Double fertilization was discovered by Nawaschin in liliaceous plants such as Lilium and Fritillaria.
What is the role of the ovary in fertilization?
The ovary is the part of the flower where fertilization occurs after the pollen tube traverses down to it.
What layer supplies nourishment to developing pollen grains?
The tapetum layer supplies nourishment to developing pollen grains.
What is Sexual Reproduction?
Sexual reproduction involves the fusion of two compatible gametes or sex cells, leading to the formation of a diploid zygote and genetically dissimilar offspring.
What are the major events in sexual reproduction?
The major events in sexual reproduction are meiosis and the fusion of gametes to form a diploid zygote.
What is syngamy?
Syngamy is the process of fusion between a haploid male gamete and a haploid female gamete, restoring the diploid condition.
What is dormancy in seeds?
Dormancy is a state of metabolic arrest that allows seeds to survive adverse environmental conditions, preventing germination even in favorable conditions.
What is the role of synergids in the female gametophyte?
Synergids are supporting haploid cells that help guide the pollen tube towards the egg cell through hair-like projections called filiform apparatus.
What are adaptations in chiropterophilous flowers?
Chiropterophilous flowers are dull colored with strong fragrance, secrete abundant nectar, and produce large amounts of edible pollen grains.
What is adventive embryony?
Adventive embryony is when embryos develop from somatic nucellus or integuments alongside the normal zygotic embryo, leading to polyembryony.
What are non-endospermic seeds?
Non-endospermic seeds, or ex-albuminous seeds, are those in which the embryo absorbs all the food reserves from the endosperm during development, resulting in the endosperm disappearing in mature seeds.
What is the helobial type of endosperm?
The helobial type of endosperm occurs when the first division of the primary endosperm nucleus is followed by a transverse wall, creating unequal cells, with subsequent free nuclear divisions.
What is Porogamy?
Porogamy is the entry of the pollen tube into the ovule through the micropyle.
What is the inner integument in seed formation?
The inner integument is a layer that surrounds the ovule and contributes to the formation of the seed coat after fertilization.
What is pollination in flowering plants?
Pollination is the transfer of pollen grains from the anther of a flower to the stigma of the same or a different flower.
Are pollination and fertilization necessary in apomixis?
No, pollination and fertilization are not necessary in apomixis.
What is the function of the filiform apparatus?
The filiform apparatus helps guide the pollen tube to the ovule.
What is Epihydrophily?
Epihydrophily is a type of pollination where pollen grains float on the water surface and reach the stigma of female flowers, as seen in plants like Vallisneria.
What is Vegetative Reproduction?
Vegetative reproduction is a form of asexual reproduction where plants reproduce through their vegetative parts, resulting in genetically identical offspring.
What is the role of compatibility in Pollen - Pistil Interaction?
Compatibility determines which pollen grains are accepted or rejected by the pistil, based on special proteins that recognize compatible pollen of the same species.
What is Entomophily?
Entomophily is a type of pollination that occurs with the help of insects, involving flowers that are large, brightly colored, and produce sweet odors and nectar.
What is Syngamy in the context of Double Fertilization?
Syngamy is the fusion of a haploid male gamete with a haploid female gamete (egg) to produce a diploid zygote.
What is a Suspensor in embryonic development?
The Suspensor is a structure formed from the suspensor initial cell that helps push the embryo into the endosperm.
What is Vegetative Propagation?
Vegetative propagation is a form of asexual reproduction in plants where new individuals are produced from vegetative parts such as roots, leaves, or stems.
What role do biotic agents play in pollination?
Biotic agents, including insects, birds, bats, and snails, help transfer pollen from one flower to another, facilitating plant reproduction and sustaining ecosystems.
What is the role of the Embryonal initial?
The Embryonal initial is the smaller cell in the two-celled proembryo that undergoes divisions to form the embryonic structures.
What is the significance of fruits in seed development?
Fruits provide nourishment to developing seeds, protect seeds in their immature condition, and develop special devices for seed dispersal.
What is the structure of a microspore?
A typical pollen grain is a non-motile, haploid, unicellular body with a single nucleus, surrounded by a two-layered wall called sporoderm.
What does pollen viability depend on?
Pollen viability depends upon environmental conditions of temperature and humidity.
What is coleoptile?
Coleoptile is the protective sheath that covers the plumule in monocot embryos.
In which part of the ovule does meiosis occur?
Meiosis occurs in the megaspore mother cell.
What part of the gynoecium determines the compatible nature of pollen grain?
The stigma determines the compatible nature of pollen grain.
What is hydrophily?
Hydrophily is the pollination mechanism where pollen is transferred by water.
What is Pollen - Pistil Interaction?
It is the interaction of pollen grains with sporophytic tissue (stigma), beginning with pollination and ending with fertilization, involving the recognition and acceptance of compatible pollen by the pistil.
What is androecium?
The male reproductive whorl of a flower, consisting of stamens.
What is an Oospore?
An Oospore is the initial zygote formed after fertilization, which develops into the embryo.
What are outbreeding devices in plants?
Outbreeding devices are mechanisms that discourage or prevent self-pollination to promote cross-pollination and increase genetic diversity, essential for evolution by natural selection.
What is Fragmentation?
Fragmentation is a method of asexual reproduction where multicellular organisms break into fragments, which can grow into new individuals, as seen in organisms like Spirogyra.
What is Tissue Culture?
Tissue culture is a method of propagating plants by using a small amount of plant tissue to grow new plants.
What is Triple Fusion in Double Fertilization?
Triple fusion is the process where the second haploid male gamete fuses with the diploid secondary nucleus to produce the primary endosperm nucleus, which develops into triploid endosperm.
What is the development of dicot embryo?
The development of a dicot embryo involves the formation of a zygote from the fertilization of an egg by a male gamete, followed by cell divisions that lead to the formation of the embryo and the surrounding structures.
What is microsporogenesis?
The process where each microspore mother cell divides meiotically to form a tetrad of haploid microspores (pollen grains).
What is the hilum in seed formation?
The hilum is the scar of the ovule that remains after the seed has formed, marking the point of attachment to the funiculus.
What is Heterostyly?
It refers to the presence of two or three forms of flowers in some plants, where stigmas and anthers are placed at different levels to prevent self-pollination.
What is Mesogamy?
Mesogamy is the entry of the pollen tube into the ovule by piercing the integuments.
What is Self Incompatibility?
It is a genetic mechanism that inhibits the germination of pollen on the stigma of the same flower, preventing self-fertilization.
In which structures is the ploidy level NOT the same?
The ploidy level is NOT the same in the secondary nucleus and endosperm.
What is Cleistogamy?
Cleistogamy is a condition where some flowers self-pollinate even before opening, often seen in underground flowers.
What is Siphonogamy?
Siphonogamy refers to the process where non-motile male gametes are carried through a hollow pollen tube to ensure fertilization takes place.
What are Chasmogamous flowers?
Chasmogamous flowers are those that open to expose their sex organs, allowing for pollination.
What is the function of the micropyle in seeds?
The micropyle is a small pore in the seed coat that allows the entry of water and oxygen during soaking.
What is the significance of the Plumule in embryonic development?
The Plumule is the part of the embryo that develops into the shoot and leaves.
What is the process of fertilization in plants?
Fertilization in plants occurs when one male gamete fuses with the egg or ovum, leading to the formation of a zygote.
What is the receptacle in a flower?
The receptacle is the base of the flower to which other floral parts are attached.
If the diploid chromosome number in a flowering plant is 12, which structure will have 6 chromosomes?
The endosperm will have 6 chromosomes.
How many haploid cells are present in a mature embryo sac?
There are seven haploid cells present in a mature embryo sac.
What is the significance of incompatibility in gamete fusion?
Incompatibility acts as a natural barrier preventing the fusion of gametes from different species, ensuring species integrity.
What is Protogyny?
It is a type of dichogamy where the gynoecium matures earlier than the androecium, also preventing self-pollination.
What is pericarp?
Pericarp is the part of the fruit that develops from the ovary wall after fertilization, typically consisting of three layers in fleshy fruits.
What is the function of germ-pores in pollen grains?
Germ-pores are thin areas in the exine that allow for the growth of the emerging pollen tube during germination.
Why are at least 20 pollen grains required to fertilize 20 ovules in a particular carpel?
At least 20 pollen grains are required because each pollen grain has 2 male gametes, and not all will successfully fertilize an ovule.
What is parthenocarpy?
Parthenocarpy is the development of fruit without fertilization.
What is the process of double fertilization?
Double fertilization involves the fusion of one male gamete with the egg cell to form the zygote and another male gamete with two polar nuclei to form the triploid endosperm.
How can polyembryony be commercially exploited?
Polyembryony can be commercially exploited by producing multiple embryos from a single fertilized ovule, leading to more plants.
What are the stages involved in the maturation of microspore into male gametophyte?
The stages include microspore formation, mitotic division to form pollen grains, and development into mature male gametophytes.
What are three devices that encourage cross-pollination in angiosperms?
Three devices include dichogamy, herkogamy, and self-incompatibility mechanisms.
What is Asexual Reproduction?
Asexual reproduction is the process resulting in the production of genetically identical progeny from a single organism, without the fusion of gametes, leading to clones that inherit the genes of the parent.