In biology Biology is the natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy, a spore is a reproductive Reproduction is the biological process by which new individual organisms are produced. Reproduction is a fundamental feature of all known life; each individual organism exists as the result of reproduction. The known methods of reproduction are broadly grouped into two main types: sexual and asexual structure that is adapted for dispersal Biological dispersal refers to a species movement away from an existing population or away from the parent organism. Through simply moving from one habitat patch to another, the dispersal of an individual has consequences not only for individual fitness, but also for population dynamics, population genetics, and species distribution. Understanding and surviving for extended periods of time in unfavorable conditions. Spores form part of the life cycles A life cycle is a period involving all different generations of a species succeeding each other through means of reproduction, whether through asexual reproduction or sexual reproduction . For example, a complex life cycle of Fasciola hepatica includes three different multicellular generations: 1) "adult" hermaphroditic; 2) sporocyst; 3) of many bacteria The bacteria ( [bækˈtɪərɪə] ; singular: bacterium)[α] are a large group of unicellular, prokaryote, microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals. Bacteria are ubiquitous in every habitat on Earth, growing in soil, acidic hot springs, radioactive waste,, plants Plants are living organisms belonging to the kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The scientific study of plants, known as botany, has identified about 350,000 extant species of plants, defined as seed plants, bryophytes, ferns and fern allies. As of 2004,, algae Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms. The largest and most complex marine forms are called seaweeds. They are photosynthetic, like plants, and "simple" because they lack the many distinct organs found in land plants, fungi A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. The Fungi (pronounced /ˈfʌndʒaɪ/ or /ˈfʌŋɡaɪ/) are classified as a kingdom that is separate from plants, animals and bacteria. One major difference is that fungal cells have cell and some protozoans Protozoa or Cornelius protozoans (from Greek πρῶτον proton "first" and ζῷα zoa "animals"; singular protozoon; are microorganisms classified as unicellular eukaryotes.[1] A chief difference between spores and seeds as dispersal units Biological dispersal refers to a species movement away from an existing population or away from the parent organism. Through simply moving from one habitat patch to another, the dispersal of an individual has consequences not only for individual fitness, but also for population dynamics, population genetics, and species distribution. Understanding is that spores have very little stored food resources compared with seeds.
Spores are usually haploid Ploidy is the number of complete sets of chromosomes in a biological cell. In humans, the somatic cells that compose the body are diploid , but sex cells (sperm and egg) are haploid. In contrast, tetraploidy (four sets of chromosomes) is a type of polyploidy and is common in plants, and not uncommon in amphibians, reptiles, and various species of and unicellular A microorganism or microbe is an organism that is microscopic (usually too small to be seen by the naked human eye). The study of microorganisms is called microbiology, a subject that began with Anton van Leeuwenhoek's discovery of microorganisms in 1675, using a microscope of his own design and are produced by meiosis In biology, meiosis is a process of reductional division in which the number of chromosomes per cell is cut in half. In animals, meiosis always results in the formation of gametes, while in other organisms it can give rise to spores. As with mitosis, before meiosis begins, the DNA in the original cell is replicated during S-phase of the cell cycle in the sporangium A sporangium is a plant, fungal, or algal structure producing and containing spores. Sporangia occur in angiosperms, gymnosperms, ferns, fern allies, bryophytes, algae, and fungi. Their spores are sometimes called sporangiospores by the sporophyte All land plants, and some algae, have life cycles in which a haploid gametophyte generation alternates with a diploid sporophyte, the generation of a plant or alga that has a double set of chromosomes. A multicellular sporophyte generation or phase is present in the life cycle of all land plants and in some green algae. For common flowering plants. Once conditions are favorable, the spore can develop into a new organism The term "organism" first appeared in the English language in 1701 and took on its current definition by 1834 (Oxford English Dictionary) using mitotic Mitosis is the process by which a eukaryotic cell separates the chromosomes in its cell nucleus into two identical sets in two nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two cells containing roughly equal shares of these cellular components. Mitosis and division, producing a multicellular Multicellular organisms are organisms that consist of more than one cell, and have differentiated cells that perform specialized functions in the organism. Most life that can be seen with the naked eye is multicellular, as are all members of the kingdoms Plantae and Animalia gametophyte The gametophyte produces male or female gametes , by a process of cell division called mitosis. The fusion of male and female gametes produces a diploid zygote, which develops by repeated mitotic cell divisions into a multicellular sporophyte. Because the sporophyte is the product of the fusion of two haploid gametes, its cells are diploid,, which eventually goes on to produce gametes A gamete is a cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. In species that produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual that produces the larger type of gamete—called an ovum (or egg)—and a.
Two gametes A gamete is a cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. In species that produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual that produces the larger type of gamete—called an ovum (or egg)—and a fuse to create a new sporophyte. This cycle is known as alternation of generations The Alternation of generations describes the life cycle of plants, fungi and protists. A multicellular diploid phase alternates with a multicellular haploid phase. The term can be confusing for people familiar only with the life cycle of a typical animal. A more understandable name would be "alternation of phases of a single generation", but a better term is "biological life cycle", as there may be more than one phase and so it cannot be a direct alternation. Haploid spores produced by mitosis Mitosis is the process by which a eukaryotic cell separates the chromosomes in its cell nucleus into two identical sets in two nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two cells containing roughly equal shares of these cellular components. Mitosis and (known as mitospores Conidia, sometimes termed conidiospores,[citation needed] are asexual, non-motile spores of a fungus; they are also called mitospores due to the way they are generated through the cellular process of mitosis. They are haploid cells genetically identical to the haploid parent, can develop into a new organism if conditions are favorable, and serve) are used by many fungi for asexual reproduction.
Many ferns, especially those adapted to dry conditions, produce diploid spores. This form of asexual reproduction is called apogamy. It is a form of apomixis In botany, apomixis is replacement of the normal sexual reproduction by asexual reproduction, without fertilization. (The original definition did not mention meiosis, although it is sometimes misquoted.) Thus "normal asexual reproduction" of plants, such as propagation from cuttings or leaves, has never been considered to be apomixis,.
Spores are the units of asexual reproduction Asexual reproduction is reproduction which does not involve meiosis, ploidy reduction, or fertilization. Only one parent is involved in asexual reproduction. A more stringent definition is agamogenesis which refers to reproduction without the fusion of gametes. Asexual reproduction is the primary form of reproduction for single-celled organisms, because a single spore develops into a new organism. By contrast, gametes are the units of sexual reproduction, as two gametes need to fuse to create a new organism.
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Evolver Long Beach returns just in time for Valentine's Day with The Love Spore , featuring readings and discussions on love and relationships plus live ...
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nzblue_fish
Sat, 13 Feb 2010 09:14:22 GM
I had the raw . spore. count data and some way to geocode it, but I now needed to transform that data into something usuable with Google maps. This was to be the main mashup. It would generate a KML (Keyhole Markup Language) file which I ...
