|
Batrachochytrium Dendrobatidis
''Batrachochytrium dendrobatidis'' ( ), also known as ''Bd'' or the amphibian chytrid fungus, is a fungus that causes the disease chytridiomycosis in amphibians. Since its discovery in 1998 by Lee Berger, the disease devastated amphibian populations around the world, in a global decline towards multiple extinctions, part of the Holocene extinction. A recently described second species, '' B. salamandrivorans'', also cause chytridiomycosis and death in salamanders. The fungal pathogens that cause the disease chytridiomycosis ravage the skin of frogs, toads, and other amphibians, throwing off their balance of water and salt and eventually causing heart failure, Nature reports. Some amphibian species appear to have an innate capacity to withstand chytridiomycosis infection due to symbiosis with ''Janthinobacterium lividum''. Even within species that generally succumb, some populations survive, possibly demonstrating that these traits or alleles of species are being subjected to evo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoosporangia
A zoospore is a motility, motile asexual spore that uses a flagellum for motion (physics), locomotion. Also called a swarm spore, these spores are created by some Protist, protists, bacteria, and fungi to propagate themselves. Diversity Flagella types Zoospores may possess one or more distinct types of flagella - tinsel or "decorated", and whiplash, in various combinations. *Tinsellated (straminipilous) flagella have lateral Protein filament, filaments known as mastigonemes perpendicular to their main axis, which allow for more surface area, and disturbance of the medium, giving them the property of a rudder, that is, used for steering. *Whiplash flagella are straight, to power the zoospore through its medium. Also, the "default" zoospore only has the propelling, whiplash flagella. Both tinsel and whiplash flagella beat in a sinusoidal wave pattern, but when both are present, the tinsel beats in the opposite direction of the whiplash, to give two axes of control of motility. Mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chytridium Confervae
''Chytridium'' is a genus of fungi in the family Chytridiaceae. With the culture and characterization of '' Chytridium olla'', the type species of the order, the limits of the Chytridiales were established. ; Names brought to synonymy: * ''Chytridium (Olpidium)'' Braun 1856, a synonym for ''Olpidium ''Olpidium'' is a fungal genus in the family Olpidiaceae. Members of ''Olpidium'' are zoosporic pathogens of plants, animals, fungi, and oomycetes. Morphology ''Olpidium'' species exist as spherical zoosporangia inside the cells of their host ...'' References * Karling JS. (1971). On Chytridium Braun, Diplochytridium n. g. and Canteria n. g. (Chytridiales). Archiv für Mikrobiologie. volume 76, pages 126–131, * Alexander Braun, 1856: Über Chytridium, eine Gattung einzelliger Schmarotzergewächse auf Algen und Infusorien (On Chytridium, a genus of unicellular parasites on algae and infusoria) External links * * Chytridiomycota genera {{Chytridiomycota-s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cisterna
A cisterna (plural cisternae) is a flattened membrane vesicle found in the endoplasmic reticulum and Golgi apparatus. Cisternae are an integral part of the packaging and modification processes of proteins occurring in the Golgi. Function Proteins begin on the cis side of the Golgi (the side facing the ER) and exit on the trans side (the side facing the plasma membrane). Throughout their journey in the cisterna, the proteins are packaged and are modified for transport throughout the cell. The number of cisterna in the Golgi stack is dependent on the organism and cell type. The structure, composition, and function of each of the cisternae may be different inside the Golgi stack. These different variations of Golgi cisternae are categorized into 3 groups; cis Golgi network, medial, and trans Golgi network. The cis Golgi network is the first step in the cisternal structure of a protein being packaged, while the trans Golgi network is the last step in the cisternal structure when the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribosome
Ribosomes ( ) are macromolecular machines, found within all cells, that perform biological protein synthesis (mRNA translation). Ribosomes link amino acids together in the order specified by the codons of messenger RNA (mRNA) molecules to form polypeptide chains. Ribosomes consist of two major components: the small and large ribosomal subunits. Each subunit consists of one or more ribosomal RNA (rRNA) molecules and many ribosomal proteins (RPs or r-proteins). The ribosomes and associated molecules are also known as the ''translational apparatus''. Overview The sequence of DNA that encodes the sequence of the amino acids in a protein is transcribed into a messenger RNA chain. Ribosomes bind to messenger RNAs and use their sequences for determining the correct sequence of amino acids to generate a given protein. Amino acids are selected and carried to the ribosome by transfer RNA (tRNA) molecules, which enter the ribosome and bind to the messenger RNA chain via an anti-co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flagellum
A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates. A microorganism may have from one to many flagella. A gram-negative bacterium '' Helicobacter pylori'' for example uses its multiple flagella to propel itself through the mucus lining to reach the stomach epithelium, where it may cause a gastric ulcer to develop. In some bacteria the flagellum can also function as a sensory organelle, being sensitive to wetness outside the cell. Across the three domains of Bacteria, Archaea, and Eukaryota the flagellum has a different structure, protein composition, and mechanism of propulsion but shares the same function of providing motility. The Latin word means " whip" to describe its lash-like swimming motion. The flagellum in archaea is called the archaellum to note its difference from the bacterial flagellum. Euk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoospores
A zoospore is a motile asexual spore that uses a flagellum for locomotion. Also called a swarm spore, these spores are created by some protists, bacteria, and fungi to propagate themselves. Diversity Flagella types Zoospores may possess one or more distinct types of flagella - tinsel or "decorated", and whiplash, in various combinations. *Tinsellated (straminipilous) flagella have lateral filaments known as mastigonemes perpendicular to their main axis, which allow for more surface area, and disturbance of the medium, giving them the property of a rudder, that is, used for steering. *Whiplash flagella are straight, to power the zoospore through its medium. Also, the "default" zoospore only has the propelling, whiplash flagella. Both tinsel and whiplash flagella beat in a sinusoidal wave pattern, but when both are present, the tinsel beats in the opposite direction of the whiplash, to give two axes of control of motility. Morphological types In eukaryotes, the four main types ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporangia
A sporangium (; from Late Latin, ) is an enclosure in which spores are formed. It can be composed of a single cell or can be multicellular. Virtually all plants, fungi, and many other lineages form sporangia at some point in their life cycle. Sporangia can produce spores by mitosis, but in nearly all land plants and many fungi, sporangia are the site of meiosis and produce genetically distinct haploid spores. Fungi In some phyla of fungi, the sporangium plays a role in asexual reproduction, and may play an indirect role in sexual reproduction. The sporangium forms on the sporangiophore and contains haploid nuclei and cytoplasm. Spores are formed in the sporangiophore by encasing each haploid nucleus and cytoplasm in a tough outer membrane. During asexual reproduction, these spores are dispersed via wind and germinate into haploid hyphae. Although sexual reproduction in fungi varies between phyla, for some fungi the sporangium plays an indirect role in sexual reproductio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operculum (botany)
In botany, an operculum () or calyptra () is a cap-like structure in some flowering plants, mosses, and fungi. It is a covering, hood or lid, describing a feature in plant morphology. Flowering plants In flowering plants, the operculum, also known as a calyptra, is the cap-like covering or "lid" of the flower or fruit that detaches at maturity. The operculum is formed by the fusion of sepals and/or petals and is usually shed as a single structure as the flower or fruit matures. The name is also used for the capping tissue of roots, the root cap. In eucalypts, (including ''Eucalyptus'' and '' Corymbia'' but not '' Angophora'') there may be two opercula - an outer operculum formed by the fusion of the united sepals and an inner operculum formed by the fusion of the sepals. In that case, the outer operculum is shed early in the development of the bud leaving a scar around the bud. In those species that lack an outer operculum, there is no bud scar. The inner operculum is she ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizoid
Rhizoids are protuberances that extend from the lower epidermal cells of bryophytes and algae. They are similar in structure and function to the root hairs of vascular land plants. Similar structures are formed by some fungi. Rhizoids may be unicellular or multicellular. Evolutionary development Plants originated in aquatic environments and gradually migrated to land during their long course of evolution. In water or near it, plants could absorb water from their surroundings, with no need for any special absorbing organ or tissue. Additionally, in the primitive states of plant development, tissue differentiation and division of labor was minimal, thus specialized water absorbing tissue was not required. The development of specialized tissues to absorb water efficiently and anchor themselves to the ground enabled the spread of plants to the land. Description Rhizoids absorb water mainly by capillary action, in which water moves up between threads of rhizoids and not through e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 were previously known as the thallophytes, a polyphyletic group of distantly related organisms. An organism or structure resembling a thallus is called thalloid, thallodal, thalliform, thalline, or thallose. A thallus usually names the entire body of a multicellular non-moving organism in which there is no organization of the tissues into organs. Even though thalli do not have organized and distinct parts ( leaves, roots, and stems) as do the vascular plants, they may have analogous structures that resemble their vascular "equivalents". The analogous structures have similar function or macroscopic structure, but different microscopic structure; for example, no thallus has vascular tissue. In exceptional cases such as the Lemnoide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphibian
Amphibians are four-limbed and ectothermic vertebrates of the class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial, fossorial, arboreal or freshwater aquatic ecosystems. Thus amphibians typically start out as larvae living in water, but some species have developed behavioural adaptations to bypass this. The young generally undergo metamorphosis from larva with gills to an adult air-breathing form with lungs. Amphibians use their skin as a secondary respiratory surface and some small terrestrial salamanders and frogs lack lungs and rely entirely on their skin. They are superficially similar to reptiles like lizards but, along with mammals and birds, reptiles are amniotes and do not require water bodies in which to breed. With their complex reproductive needs and permeable skins, amphibians are often ecological indicators; in recent decades there has been a dramatic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keratin
Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, horns, claws, hooves, and the outer layer of skin among vertebrates. Keratin also protects epithelial cells from damage or stress. Keratin is extremely insoluble in water and organic solvents. Keratin monomers assemble into bundles to form intermediate filaments, which are tough and form strong unmineralized epidermal appendages found in reptiles, birds, amphibians, and mammals. Excessive keratinization participate in fortification of certain tissues such as in horns of cattle and rhinos, and armadillos' osteoderm. The only other biological matter known to approximate the toughness of keratinized tissue is chitin. Keratin comes in two types, the primitive, softer forms found in all vertebrates and harder, derived forms found only among saur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.svg "Click for more on -> Cisterna")
.png "Click for more on -> Amphibian")
