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Punctelia Subalbicans
''Punctelia subalbicans'' is a species of foliose lichen in the family Parmeliaceae. It is found in Australia and New Zealand, where it grows on the bark of various tree species. Taxonomy The lichen was first described as a new species by James Stirton in 1878. The holotype was collected by botanist James Drummond near Swan River in Western Australia. David Galloway suggested moving the taxon to the genus '' Parmelina'' in 1983, but a year later he and John Alan Elix transferred it to the genus ''Punctelia''. The taxon ''Punctelia pallescens'', described by Syo Kurokawa in 1999 as a new species from western Australia, was later determined to be identical chemically and morphologically with ''P. subalbicans'', and it is now considered a synonym. Description The pale greenish-grey thallus of ''Punctelia subalbicans'' typically measures in diameter. Lobes comprising the thallus are irregularly shaped with rounded tips and are scalloped with dark margins; they are usual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphology (biology)
Morphology is a branch of biology dealing with the study of the form and structure of organisms and their specific structural features. This includes aspects of the outward appearance (shape, structure, colour, pattern, size), i.e. external morphology (or eidonomy), as well as the form and structure of the internal parts like bones and organs, i.e. internal morphology (or anatomy). This is in contrast to physiology, which deals primarily with function. Morphology is a branch of life science dealing with the study of gross structure of an organism or taxon and its component parts. History The etymology of the word "morphology" is from the Ancient Greek (), meaning "form", and (), meaning "word, study, research". While the concept of form in biology, opposed to function, dates back to Aristotle (see Aristotle's biology), the field of morphology was developed by Johann Wolfgang von Goethe (1790) and independently by the German anatomist and physiologist Karl Friedrich Burdach ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrometre
The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Units (SI) equalling (SI standard prefix "micro-" = ); that is, one millionth of a metre (or one thousandth of a millimetre, , or about ). The nearest smaller common SI unit is the nanometre, equivalent to one thousandth of a micrometre, one millionth of a millimetre or one billionth of a metre (). The micrometre is a common unit of measurement for wavelengths of infrared radiation as well as sizes of biological cells and bacteria, and for grading wool by the diameter of the fibres. The width of a single human hair ranges from approximately 20 to . The longest human chromosome, chromosome 1, is approximately in length. Examples Between 1 μm and 10 μm: * 1–10 μm – length of a typical bacterium * 3–8 μm – width of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascospore
An ascus (; ) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some genera or species can occur in numbers of one (e.g. ''Monosporascus cannonballus''), two, four, or multiples of four. In a few cases, the ascospores can bud off conidia that may fill the asci (e.g. ''Tympanis'') with hundreds of conidia, or the ascospores may fragment, e.g. some ''Cordyceps'', also filling the asci with smaller cells. Ascospores are nonmotile, usually single celled, but not infrequently may be coenocytic (lacking a septum), and in some cases coenocytic in multiple planes. Mitotic divisions within the developing spores populate each resulting cell in septate ascospores with nuclei. The term ocular chamber, or oculus, refers to the epiplasm (the portion of cytoplasm not used in ascospore formation) that is surrounded by the "bourrelet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apothecia
An ascocarp, or ascoma (), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascocarps are most commonly bowl-shaped (apothecia) but may take on a spherical or flask-like form that has a pore opening to release spores (perithecia) or no opening (cleistothecia). Classification The ascocarp is classified according to its placement (in ways not fundamental to the basic taxonomy). It is called ''epigeous'' if it grows above ground, as with the morels, while underground ascocarps, such as truffles, are termed ''hypogeous''. The structure enclosing the hymenium is divided into the types described below (apothecium, cleistothecium, etc.) and this character ''is'' important for the taxonomic classification of the fungus. Apothecia can be relatively large and fleshy, whereas the others are microscopic—about the size of flecks of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soralia
Soredia are common reproductive structures of lichens. Lichens reproduce asexually by employing simple fragmentation and production of soredia and isidia. Soredia are powdery propagules composed of fungal hyphae wrapped around cyanobacteria or green algae. These can be either scattered diffusely across the surface of the lichen's thallus Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms ..., or produced in localized structures called soralia. Fungal hyphae make up the basic body structure of lichen. The soredia are released through openings in the upper cortex of the lichen structure. After their release, the soredia disperse to establish the lichen in a new location. References Fungal morphology and anatomy Lichenology {{lichen-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isidia
An isidium is a vegetative reproductive structure present in some lichens. Isidia are outgrowths of the thallus surface, and are corticated (i.e., containing the outermost layer of the thallus), usually with a columnar structure, and consisting of both fungal hyphae (the mycobiont) and algal cells (the photobiont). They are fragile structures and may break off and be distributed by wind, animals, and splashing raindrops. In terms of structure, isidia may be described as warty, cylindrical, clavate (club-shaped), scale-like, coralloid (coral-shaped), simple, or branched. Examples of isidiate lichens include members of the genera ''Parmotrema'' and ''Peltigera''. See also Soredium Soredia are common reproductive structures of lichens. Lichens reproduce asexually by employing simple fragmentation and production of soredia and isidia. Soredia are powdery propagules composed of fungal hyphae wrapped around cyanobacteria o ... References External linksAscomycetes glossary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propagule
In biology, a propagule is any material that functions in propagating an organism to the next stage in its life cycle, such as by dispersal. The propagule is usually distinct in form from the parent organism. Propagules are produced by organisms such as plants (in the form of seeds or spores), fungi (in the form of spores), and bacteria (for example endospores or microbial cysts). In disease biology, pathogens are said to generate infectious propagules, the units that transmit a disease. These can refer to bacteria, viruses, fungi, or protists, and can be contained within host material. For instance, for influenza, the infectious propagules are carried in droplets of host saliva or mucus that are expelled during coughing or sneezing. In horticulture, a propagule is any plant material used for the purpose of plant propagation. In asexual reproduction, a propagule is often a stem cutting. In some plants, a leaf section or a portion of root can be used. In sexual reproduction, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizine
In lichens, rhizines are multicellular root-like structures, arising mostly from the lower surface. A lichen with rhizines is termed rhizinate, while a lichen lacking rhizines is termed erhizinate. Rhizines serve only to anchor the lichen to their substrate; they do not absorb nutrients as do plant roots. Characteristics of the rhizines are used to identify lichens, for example: whether they are dense or sparse, whether they are uniformly distributed or clumped in specific areas, and whether they are straight or branched. Only foliose lichens may possess rhizines, not crustose or fruticose lichens, which lack a lower cortex. Rhizohyphae are a type of attachment structure on some lichens. Rhizohyphae are more slender than rhizines and are one cell thick in diameter. Rhizohyphae often occur as a felt-like hyphal mass. See also *Rhizoid Rhizoids are protuberances that extend from the lower epidermal cells of bryophytes and algae. They are similar in structure and function to the ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cream (colour)
Cream is the colour of the cream produced by cattle grazing on natural pasture with plants rich in yellow carotenoid pigments, some of which are incorporated into the fresh milk (specifically, the butterfat). This gives a yellow tone to otherwise-white milk at higher fat concentrations (so the colour of dairy cream could be considered partway between the colours of natural cow’s milk and butter). Cream is the pastel colour of yellow, much as pink is to red. By mixing yellow and white, cream can be produced. The first recorded use of ''cream'' as a colour name in English was in 1590. In nature ;Birds * The cream-coloured courser * The cream-coloured woodpecker ;Mammals * The cream-coloured giant squirrel In human culture Art * Cream is used as a skin tone in some forms of art, mostly anime. It is also used to describe the general skin tone of East and South East Asia. Clothing * Men's white tuxedo jackets are usually a shade of cream or ivory to better stand out again ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buff (colour)
Buff (latin ''bubalinus'') is a light brownish yellow, ochreous colour, typical of buff leather. Buff is a mixture of yellow ochre and white: two parts of white lead and one part of yellow ochre produces a good buff, or white lead may be tinted with French ochre alone. As an RYB quaternary colour, it is the colour produced by an equal mix of the tertiary colours citron and russet. Etymology The first recorded use of the word ''buff'' to describe a colour was in ''The London Gazette'' of 1686, describing a uniform to be "...a Red Coat with a Buff-colour'd lining". It referred to the colour of undyed buffalo leather, such as soldiers wore as some protection: an eyewitness to the death in the Battle of Edgehill (1642) of Sir Edmund Verney noted "he would neither put on arms rmouror buff coat the day of the battle". Such buff leather was suitable for ''buffing'' or serving as a ''buffer'' between polished objects. It is not clear which bovine "''buffalo''" referred to, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hymenium
The hymenium is the tissue layer on the hymenophore of a fungal fruiting body where the cells develop into basidia or asci, which produce spores. In some species all of the cells of the hymenium develop into basidia or asci, while in others some cells develop into sterile cells called cystidia (basidiomycetes) or paraphyses (ascomycetes). Cystidia are often important for microscopic identification. The subhymenium consists of the supportive hyphae from which the cells of the hymenium grow, beneath which is the hymenophoral trama, the hyphae that make up the mass of the hymenophore. The position of the hymenium is traditionally the first characteristic used in the classification and identification of mushrooms. Below are some examples of the diverse types which exist among the macroscopic Basidiomycota and Ascomycota. * In agarics, the hymenium is on the vertical faces of the gills. * In boletes and polypores, it is in a spongy mass of downward-pointing tubes. * In puffballs, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
