how does the plant Equisetum reproduce?
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Sexual reproduction-Sexual dispersal in Equisetum occurs by means of spores.  Equisetum spores are green, spherical, and have thin spore walls.  Each Equisetum spore has four unique strap-like structures called elaters attached to the spore surface at a common point.  These elaters are hygroscopic (i.e. they expand and contract with changes in humidity) and probably function to help disperse the spores.Equisetum spores are short-lived and can germinate within 24 hours of release from the cone.  After 5-17 days, depending on humidity, they are no longer capable of germination .In nontropical species (the majority of Equisetum ), the spores are produced over a short period of time during the growing season .Equisetum gametophytes appear to require a substrate of recently exposed bare mud in order to become established .Like pioneer species, they rapidly attain sexual maturity and are adversely affected by competition from bryophytes and vascular plants .The resulting inefficiency of spore germination and gametophyte reproduction in non-pioneer situations probably limits gene flow and leads the high degree of genetic divergence found between Equisetum populations. Therefore, sexual reproduction in Equisetum is limited to rather narrow ecological conditions and this limits the dispersal ability of Equisetum via spores.\n\nAsexual Reoroduction-Equisetum species have a remarkable ability to reproduce vegetatively.  This helps to compensate for the inefficiency of spore reproduction.  An extensive rhizome system allows Equisetum species to rapidly colonize disturbed areas .This ability gives Equisetum a distinct advantage over species requiring seed establishment or which have slow-growing rhizomes .For instance, the widespread creation of roadside ditches in America has created significant new habitat for some Equisetum species.  This is because the soil in ditch habitats tends to be moist and the rhizomatous growth of Equisetum species allows them to survive and thrive under the conditions of sediment accumulation that are characteristic of ditches .The ability of Equisetum to survive and spread in areas of heavy sediment accumulation was dramatically demonstrated after the 1912 eruption of Katmai Volcano in Alaska.  In studies of vegetational recovery from the volcanic tephra (ash and silt) deposited by this eruption, E. arvense was found to be the most successful herb.  It was able to penetrate as much as one meter of tephra, more than any other herbaceous species, and colonize large areas via rapid rhizomatous growth The remarkable ability of Equisetum to prosper under disturbed conditions was also demonstrated after the eruption of Mount St. Helens in 1980 when Equisetum formed almost monotypic stands in the newly deposited tephra .The deep rhizome system of Equisetum also allows these plants to survive fire and rapidly recolonize burned-over sites .It is probable that the vigorous and extensive rhizomatous habit of Equisetum has been very important to the long term survival and spread of the genus .\n\nVegetative reproduction - Fragmentation of rhizomes and stems allows Equisetum to disperse readily in suitable habitats where there is sufficient moisture.  Even the aerial stem fragments can sprout and form new colonies .Hence, vegetative reproduction allows Equisetum clones to persist and spread even in the absence of sexual reproduction .\nVegetative reproduction probably accounts for the widespread occurrence and persistence of common Equisetum hybrids even where one or both of the parents are absent .  This is because hybrids are generally sterile and hence are without means of sexual reproduction.  The rhizome system of a vigorous hybrid clone theoretically has the ability to maintain dense colonies within limited areas for long periods.  Fragmentation and transport of rhizomes and stems then has the potential to disperse the clone from the site of the original hybridization .  This would account for the abundance of Equis
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Not sure what you are asking here.\nIf you want your ginkgos to reproduce, you're going to need a female tree... and if there aren't any male ginkgoes nearby, you'll need to plant one of those too (the male and female bits are separate -- they don't grow on the same tree!)\n\nAre you sure you want your ginkgoes to reproduce?  Ginkgo fruit is really messy -- it falls off the tree and goes splat, and rotten ginkgo fruit doesn't smell good!
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I would have to answer that you're asking the wrong question!  \n\nThe explanation of how a plant or animal can develop asexual reproduction isn't going to help you better understand incremental changes via evolution; what you really need to understand is how a plant or animal can develop sexual reproduction. \n\nLooking at the first, microbiological life, asexual reproduction - i.e. cell division or 'budding' -  was the first and most essential form of reproduction. It took century upon century for more complex life to develop and specialize; and, for the mechanisms of sexual reproduction to develop and become established. \n\nThe change from asexual to sexual reproduction would indeed have been  massive, but it doesn't follow that it had to be sudden. When scientists look at species and evolution, they will generally say that one species was more successful at adapting to their environment than another. \n\nIt seems that the ancestors of many plants and animals developed sexual reproduction mechanisms, and they were more successful in competing with other animals for food/territory, over an extended period of time. The less successful ones died out long ago.\n\nSo - it may not be totally accurate to say, "reproduction either works or it doesn't." A better statement would be, "evolutionarily speaking, changes in species over time may cause one method of reproduction to become less successful than another."  \n\nHaving said that: there are other scientists who agree that evolution isn't always slow and gradual; they argue that sometimes evolution happens occasionally in a sudden and dramatic way, when one species splits to become new species - generally the new species are created when one population becomes separated by geographic boundaries. \n\nI'd strongly suggest reading the Wikipedia article (linked below) on Stephen Jay Gould for an evolutionary point of view which counters the slow evolution methodologies advocated by Dawkins; as well as the articple on evolution itself - which looks at the development of the understanding of evolutionary principles and their historical context.
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Double fertilization isn't seen in gymnosperms in the true sense of the word. This is because the endosperm in gymnosperms is a prefertilization product which is haploid. In angiosperms, the sperm nuclei are involved in the formation of both Primary Endosperm Nucleus or PEN from the central cell as well as fertilization of ovum or egg. Therefore it is called double fertilization.
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pteridophytes are seedless vascular plants. They reproduce by spores and they contain xylem and phloem.
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FLowers are the sex organs of the plant.  They are pollinated and make seeds.
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Sea cucumbers can reproduce either asexually by budding or sexually by releasing gametes into the water.  Check out Wikipedia...they have some basic info.
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Assuming your species is diploid, it goes like this:\n\nSupposing there is a field of red, pink and white flowers. Red flowers have genotype RR, pink Rr or rR, and white rr. \n\nYou count the number of each kind of flower. It turns out there are 150 red-flowered plants, 480 pink, and 170 white ones. \n\nTherefore there are 2*(150+480+170) = 1600 alleles out there. There are 300 Rs in the red plants, 480 in the pink ones and 0 in the white. Added together there are 780. 780/1600 = 0.4875, so the frequency of the R allele is 48.75%\n\nAs for the r allele, there are 0 in the red-flowered plants, 480 in the pink, and 340 in the white. Added together, there are 820. 820/1600 is 51.25%.\n\nAs a double check, 48.75% + 51.25% = 100%
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diploidization\n\ndoubling of chromosome no.\nthis method is usually implied in plants to double their chromosomal configuration
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Nearly all animals undergo some form of sexual reproduction. Adults are diploid or occasionally polyploid. They have a few specialized reproductive cells, which undergo meiosis to produce smaller motile spermatozoa or larger non-motile ova. These fuse to form zygotes, which develop into new individuals.\n\nMany animals are also capable of asexual reproduction. This may take place through parthenogenesis, where fertile eggs are produced without mating, or in some cases through fragmentation.\n\nA zygote initially develops into a hollow sphere, called a blastula, which undergoes rearrangement and differentiation. In sponges, blastula larvae swim to a new location and develop into a new sponge. In most other groups, the blastula undergoes more complicated rearrangement. It first invaginates to form a gastrula with a digestive chamber, and two separate germ layers - an external ectoderm and an internal endoderm. In most cases, a mesoderm also develops between them. These germ layers then differentiate to form tissues and organs.\n\nAnimals grow by indirectly using the energy of sunlight. Plants use this energy to turn air into simple sugars using a process known as photosynthesis. These sugars are then used as the building blocks which allow the plant to grow. When animals eat these plants (or eat other animals which have eaten plants), the sugars produced by the plant are used by the animal. They are either used directly to help the animal grow, or broken down, releasing stored solar energy, and giving the animal the energy required for motion. This process is known as glycolysis.
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Plants which reproduce without seeds appeared first in the history of the Earth.  Plants with seeds appeared much later.
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Same as any other plant really.  Storage, transportation, photosynthesis, absorption, reproduction
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MALE part of FLOWER: consists of anther and filament. Anter houses and produces pollen (sperm)-meiosis here. Filament holds the anther to the flower. \n\nthe main purpose is for reproduction.
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Asexual reproduction is cloning. A piece of a plant may root or sprout and grow into a new plant which is genetically identical with the parent.  \n\nSexual reproduction results in a new plant which contains genetic material from two parents, but which is not genetically identical with either one.   These new plants may be able to adapt more successfully to environmental changes than their parents could.\n     To live and multiply on land, plants needed to evolve new structures and methods for reproduction.  An important advance was the development of the flower, a structure which allowed widespread scattering of its pollen and yet provided a stable, nurturing environment in the ovary for developing seeds.  Pollen could be carried from flower to flower by insects, the wind, or, sometimes, birds.  \n\n     The seed was another important innovation, as significant for plants as the amniotic egg was for land animals.  Seeds would form when the chromosomes of the parents were united in the ovary.  A seed is a compact package made of a cell capable of growing into a plant, food to help the plant get started, and, in angiosperms, a seed coat that protected the seed from dehydration  and  damage in the environment.  Properly protected seeds could survive until conditions favored their development.  In the deserts today, some seeds may lie dormant for many years until the rains come and provide conditions in which the seeds may germinate and grow into plants.  Some seeds also are contained in, or attached to, structures which help the seeds to be carried to other places that may be suitable for them.
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I can assure you that this is absolutely not biologically possible.  Members of different species cannot reproduce and produce viable offpsring together, according to the classical definition of a species.
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A corm is a short, thick, vertical underground stem that survives from one season to the next in a dormant state. The second season it produces one or more aerial stems and also one or more new corms. The new corms store food produced by the growing plant and then go through the next dormant period to produce their own plants and corms the following season. The “bulbs' of gladiolus are actually corms.\n\nPart 2 of your question\n\nVegetative reproduction is a type of asexual reproduction found in plants also called vegetative propagation or vegetative multiplication. \nThe problem of sex\n\nIn sexual reproduction, a new organism is formed by the fusion of two gametes. It is to be contrasted with asexual reproduction, in which females produce offspring without any male contribution; the female's gametes develop directly into female offspring. \n\n• In sexual reproduction, the sex cells - eggs and sperm or pollen - are produced by a reduction division and the gametic fusion restores the original chromosome complement. \n\n• In asexual reproduction, there is either no reduction division (apomixis) or the product cells of one individual's reduction division fuse together again (automixis). Asexual reproduction is rare, but occurs in species such as dandelions (pictured opposite).\n\nIt is easy for a mutation to convert meiosis into mitosis, and thus a sexually reproducing into an asexually reproducing female. \n\nIf the loss of sex would be relatively easy, why is sex maintained? \n\nAlthough some species do reproduce asexually, the majority are sexual. So there is probably a selective advantage to sex in most species. \n\nThis advantage, moreover, must be large, because it has to overcome an automatic two-fold cost of sex, relative to asexual reproduction.
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Asexual reproduction\n\n\nAsexual reproduction is the biological process by which an organism creates a genetically-similar or identical copy of itself without a contribution of genetic material from another individual. Bacteria divide asexually via binary fission; viruses take control of host cells to produce more viruses; Hydras (invertebrates of the order Hydroidea) and yeasts are able to reproduce by budding. These organisms do not have different sexes, and they are capable of "splitting" themselves into two or more individuals. Some 'asexual' species, like hydra and jellyfish, may also reproduce sexually. For instance, most plants are capable of vegetative reproduction—reproduction without seeds or spores—but can as well reproduce sexually. Likewise, bacteria may exchange genetic information by conjugation. Other ways of asexual reproduction include fragmentation and spore formation that involves only mitosis.\n\n\nSexual reproduction\n\nSexual reproduction is a biological process by which organisms create descendants that have a combination of genetic material contributed from two (usually) different members of the species. Each of two parent organisms contributes half of the offspring's genetic makeup by creating haploid gametes. Most organisms form two different types of gametes. In these anisogamous species, the two sexes are referred to as male (producing sperm or microspores) and female (producing ova or megaspores). In isogamous species the gametes are similar or identical in form, but may have separable properties and then may be given other different names. For example, in the green alga, Chlamydomonas reinhardtii, there are so-called "plus" and "minus" gametes. A few types of organisms, such as ciliates, have more than two kinds of gametes.\n\nHumans, most animals, and plants reproduce sexually. Sexually-reproducing organisms have two sets of genes for every trait (called alleles). Offspring inherit one allele for each trait from each parent, thereby ensuring that offspring have a combination of the parents' genes. Having two copies of every gene, only one of which is expressed, allows deleterious alleles to be masked, an advantage believed to have led to the evolutionary development of diploidy (Otto and Goldstein).