Vascular plant spores are always haploid and vascular plants are either homosporous or heterosporous. Their chief advantage is that, of all forms of progeny, spores require the least energy and materials to produce. Also, spores are less subject to animal predation than seeds because they contain almost no food reserve however they are more subject to fungal and bacterial predation. In the case of spore-shedding vascular plants such as ferns, wind distribution of very light spores provides great capacity for dispersal. Unlike eukaryotic spores, endospores are primarily a survival mechanism, not a reproductive method, and a bacterium only produces a single endospore. The endospores of certain bacteria are often incorrectly called spores, as seen in the 2001 anthrax attacks, where the media called anthrax endospores "anthrax spores". Spores are usually produced in large numbers to increase the chance of a spore surviving. Seeds, therefore, are more resistant to harsh conditions and require less energy to start mitosis.
However, the terms are somewhat interchangeable when referring to gametes.Ī chief difference between spores and seeds as dispersal units is that spores have very little stored food resources compared with seeds, and thus require more favorable conditions in order to successfully germinate. In common parlance, the difference between "spore" and " gamete" (both together called gonites) is that a spore will germinate and develop into a sporeling, while a gamete needs to combine with another gamete before developing further. Statismospore are not actively discharged from the fungal fruit body, similarly to a puffball. Ballistospore are actively discharged from the body of a fungal fruit (such as a mushroom). Autospore cannot move and cannot develop flagella. Aplanospore cannot move, but may potentially grow flagella. Zoospore can move by means of one or more flagella, and can be found in some algae and fungi. Spores can be differentiated by whether they can move or not. Mitosporic fungi are also known as anamophic fungi (compare teleomorph or deuteromycetes). An example is the parent of gametophytes of the higher vascular plants ( angiosperms and gymnosperms)-the microspores (give rise to pollen) and megaspores (or macrospores) (give rise to ovules) found in flowers and cones these plants accomplish dispersal by means of seeds.Ī mitospore (conidium, conidiospore) is an asexually produced propagule, the result of mitosis. Meiospores are the product of meiosis (the critical cytogenetic stage of sexual reproduction), meaning that they are haploid, and give rise to a haploid daughter cell(s) or a haploid individual. Since fungi are often classified according to their spore-producing structures, these spores are often characteristic of a particular taxon of the fungi, such as Ascomycota or Basidiomycota. In fungi and fungus-like organisms, spores are often classified by the structure in which meiosis and spore production takes place, such as a telium, ascus, basidium, or oogonium, which produce teliospore, ascospores, basidiospores, and oospores, respectively. In fungi, chlamydospores are thick-walled resting spores, and zygospores are thick-walled resting spores (hypnozygotes) of zygomycetous fungi which are produced by sexual gametocystogamy and can give rise to a conidiophore ("zygosporangium") with asexual conidiospores. This article has been tagged since July 2007.ĭiaspores are dispersal units of fungi, mosses, ferns, fern allies, and some other plants. If a more appropriate WikiProject or portal exists, please adjust this template accordingly. WikiProject Biology may be able to help recruit one.
This article or section is in need of attention from an expert on the subject. Unsourced material may be challenged and removed. Please help improve this article by adding reliable references. This article needs additional citations for verification. Spores can be classified in several ways. The term derives from the ancient Greek word σπορα ( "spora"), meaning a seed. Fungi that produce spores are known as sporogenous, and those that do not are asporogenous. The term can also be loosely applied to some animal resting stages. The term spore may also refer to the dormant stage of some bacteria or archaea however these are more correctly known as endospores and are not truly spores in the sense discussed in this article. By contrast, gametes are the units of sexual reproduction, as two gametes need to fuse to create a new organism. Spores are the units of asexual reproduction, because a single spore develops into a new organism. Haploid spores produced by mitosis (known as mitospores) are used by many fungi for asexual reproduction. This cycle is known as alternation of generations, but a better term is "biological life cycle", as there may be more than one phase and so it cannot be a direct alternation. Two gametes fuse to create a new sporophyte.
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