What is a pollen tube?
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POLLEN TUBE\nA tube that grows from a pollen grain on the stigma of a flower down through the style into the ovary.\n\nS: (n) pollen tube ((botany) a slender tubular outgrowth from a pollen grain when deposited on the stigma for a flower; it penetrates the style and conveys the male gametes to the ovule)
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i'd like to take this time to give a biology lesson. you/everybody else is horny because its spring time. the pollenation affects hormones.
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the egg stays where it is - in the ovary. it turns into seed there. so the pollen must germinate (into a structure called pollen tube) and this tube grows through the pistil and delivers the germ cells to fertilize the egg. cut open a ripening seed pod of a flower and u will see the growing seeds. or imagine a green pepper cut open or green peas in the pod -  the seeds are attached to something that is called placenta, actually. and before fertilization they were not seeds but eggs. and through this place of attachment they were fertilized. it is not like human egg that itself travels from ovary to uterus and gets fertilized on the way.
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The capacitated spermatozoon and the oocyte meet and interact in the ampulla of the fallopian tube. In mammals, binding of the spermatozoon to the zona pellucida, an extracellular layer surrounding the oocyte, initiates the acrosome reaction. This process releases the enzyme hyaluronidase, which digests the matrix of hyaluronic acid in the vestments surrounding the oocyte. Fusion between the sperm and oocyte plasma membranes follows, allowing the entry of the sperm nucleus, mitochondria, centriole and flagellum into the oocyte. Once the ovum fuses with a single sperm cell, its cell membrane changes, preventing fusion with other sperm.\n\nThis process ultimately leads to the formation of a diploid cell called a zygote. When the zygote reaches the uterus and implants in the endometrium, the female is said to be pregnant.\n\nIf fertilisation takes place, the sperm usually meet the ovum in the fallopian tube, requiring the sperm cells to swim from the upper vagina through the cervix and across the length of the uterus before reaching the fallopian tube—a considerable distance compared to the size of the sperm cell.\n\n\nFertilization in plants\n\nAfter the pistil is pollinated, the pollen grain germinates in a response to a sugary fluid secreted by the mature stigma. From each pollen grain, a pollen tube grows out attempting to travel into the ovary by creating a path. The vegetative and generative nuclei of the pollen grain pass into its respective pollen tube. The growth of the pollen tube is controlled by the vegetative nucleus. Enzymes are secreted to digest the tissue of the stigma a style as the polen tube grows. The pollen tube does not directly reach the ovary in a straight line. It travels near the skin of the style and curls to the bottom of the ovary, then near the receptacle, it breaks through the ovule through the microphyle (an opening in the ovule wall) and reaches the ovum to fertilise it. This is the point when fertilisation actually occurs. After being fertilised, the ovary starts to swell and becomes a fruit.\n\nWith multi-seeded fruits, multiple grains of pollen are necessary for syngamy with each ovule. The process is easy to visualise if one looks at maize silk, which is the female flower of corn. Pollen from the tassel (the male flower) falls on the sticky external portion of the silk, and then pollen tubes grow down the silk to the attached ovule. The dried silk remains inside the husk of the ear as the seeds mature; if one carefully removes the husk, the floral structures may be shown. The development of the flesh of the fruit is proportional to the percentage of fertilised ovules. For example, with watermelon, about a thousand grains of pollen must be delivered and spread evenly on the three lobes of the stigma to make a normal sized and shaped fruit.
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A flagellum (plural, flagella) is a whip-like organelle that many unicellular organisms, and some multicellular ones, use to move about. They may also be involved in other processes. The name actually covers three different structures, found in each of the three domains. Bacterial flagella are helical filaments that rotate like screws. Archaeal flagella are superficially similar, but are different in many details and considered non-homologous. Eukaryotic flagella - those of animal, plant, and protist cells - are complex cellular projections that lash back and forth. Sometimes the last are called cilia or undulipodia to emphasize their distinctiveness.
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The stamen (anther portion) of the flower produces pollen.
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When pollen fertilise with stigma, resulting in two seeds in the same fruit.
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Every flower is a terminal branch consisting of a modified stem, the floral axis, or receptacle. The floral axis bears one to four types of specialized appendages, or modified leaves, usually arranged in whorls in the more advanced flowers and spirally arranged in the more primitive ones. In a typical flower the outermost whorl, the calyx, consists of a number of sepals that protect the flower bud before it blooms. The next whorl on the floral receptacle, the corolla, is composed of a number of petals, often bearing nectar-producing glands that aid in attracting pollinators (see Pollination). The next whorl, the androecium, consists of a number of stamens that produce in anthers the pollen necessary for reproduction. Two whorls of stamens may be present. The next, or innermost, whorl of the flower, called the gynoecium, consists of several carpels frequently fused to form a pistil. Each carpel contains at least one placenta to which are attached ovules, or immature seeds. The calyx and corolla are collectively known as the perianth.
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Plants have one large vacuole. Animals have many vacuoules. Plants have a cell wall and chloroplasts. Animanls have neither. Animals have centrioles. Plants do not. This is the complete list of the differences.
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It's an oversimplification to say that pollen is a plant's sperm:\n\nPollen grains are structures that house the male gametophyte generation of angiosperms and gymnosperms (seed plants).  They are also the vehicles in which the male gamete genetic code is carried to the female gamete.  Pollen grains develop in the anther in angiosperms.  It travels and is deposited on the stigma of a receptive flower.  In gymnosperms, pollen develops in the male cone, travels, and fertilizes the ovules in the female cones to produce seeds.  Each pollen grain consists of the two celled male haploid plant enclosed in a thickened wall.
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Because is a part of a plant and the apparatus of Golgi is an animal structures. They are not cloroplast because it is a root.
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Well, we would have to know what plant you are referring to, now wouldn't we?\n\nBut generally, plants that are exclusively pollinated by insects would have a flower structure that would make it difficult for the pollen to be blown about by the wind.  These would be flowers that were deep and narrow, enclosing the anthers.  And they would generally have an area where nectar is secreted and held, so as to attract insects.  Other plants might have flowers that permitted wind pollination, but might also have flowers structured to take advantage of insect activity in a similar manner.\n\nThere are a very great many plants that are pollinated by insects, especially bees, but which can also pollinate by wind, by animals such as hummingbirds, even by water.
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How ironic; spent half the night figuring this out too... here's some of my notes\n\n•2n or not 2n: The story of the sporophyte\n\n1.gametophyte definition – “In plants, the haploid (n), gamete producing generation, which alternates with the diploid (2n) sporophyte.”\n2.sporophyte definition – “the spore producing, diploid(2n)phase in the life cycle of a plant having alternating generations.”\n3.Gametophytes and sporophytes don’t always look the same.\n4.the dominance of each differs in the phyla.\n5.With increasing complexity: the gametophyte becomes LESS dominant while the sporophyte becomes MORE dominant.\n6.In mosses, the Sporophyte is parasitic upon gametophyte. In other words, what we largely see is a photosynthetic and free living gametophyte supporting a sporophyte. \n7.However, evolution has favoured the opposite, on the whole sporophytes are large and the gametophyte small.  For example, in conifers, the gametophyte is hidden within an acorn and the sporophyte is depending on other organisms to use the acorn as food and release the gametophyte. Moreover, angiosperms have reduced gametophytes to ovules and pollen. \n\nHope this helps?
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Parts of a flower:\n- carpel, female; stigma, style & ovary;\n- stamen, male; anther & filament;\n- calyx, flower bud protection; sepals;\n- corolla; PETALS & nectaries (if present).\n\n'Petals' is a  scientific name, they form part of the corolla.\nLook here:
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the egg called ovum.....\n\nmillions of sperms are transferred from the male body to the female vagina....\n\nsperms swim through the cervix to the female uterus.....\n\nsperms swim towards the ovum in the Fallopian tube...\n\nfertilisation occurs in the fallopian tube\n\nonly one sperm will fuse with one ovum to produce a zygote\n\nthe zygote produced divides many times and develops into an embryio on its way to the uterus\n\nfinally, the embryio implants itself to the uterus wall which is rich with blood.....\n\nI hope it helps you with your homework!
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The epidiymis connects the testicles with the vas deferens (the tubes that carry sperm).
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The Flower:\nThe flower is the reproductive unit of some plants (angiosperms). Parts of the flower include petals, sepals, one or more carpels (the female reproductive organs), and stamens (the male reproductive organs). \nThe Female Reproductive Organs:\nThe pistil is the collective term for the carpel(s). Each carpel includes an ovary (where the ovules are produced; ovules are the female reproductive cells, the eggs), a style (a tube on top of the ovary), and a stigma (which receives the pollen during fertilization). \n\nThe Male Reproductive Organs:\nStamens are the male reproductive parts of flowers. A stamen consists of an anther (which produces pollen) and a filament. The pollen consists of the male reproductive cells; they fertilize ovules. \n\nFertilization:\nPollen must fertilize an ovule to produce a viable seed. This process is called pollination, and is often aided by animals like bees, which fly from flower to flower collecting sweet nectar. As they visit flowers, they spread pollen around, depositing it on some stigmas. After a male's pollen grains have landed on the stigma during fertilization, pollen tubes develop within the style, burrowing down to the ovary, where the sperm fertilizes an ovum (an egg cell), in the ovule. After fertilization, the ovule develops into a seed in the ovary. \n\nTypes of Flowers:\nSome flowers (called perfect flowers) have both male and female reproductive organs; some flowers (called imperfect flowers) have only male reproductive organs or only female reproductive organs. Some plants have both male and female flowers, while other have males on one plant and females on another. Complete flowers have stamens, a pistil, petals, and sepals. Incomplete flowers lack one of these parts. \n\nto find an extensive biology of plants please visit:\nhttp://users.pandora.be/educypedia/education/plantbiology.htm