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What morphological structure is responsible for bacteria motility?
Wiki User
∙ 11y ago
Bacteria commonly get their motility from an external structure(s) called a flagellum (if they have many, the plural form is flagella). Other motile bacteria have a cellular shape as a spiral (screw). The full mechanism of their motility is not understood. There are many types of spiral bacteria, some with and others without any flagellum.
There are also bacteria (e.g. Magnetotactic bacteria and others) that will orient directionally, though not self-induced. They contain minerals such as iron in their cellular structure that orients or moves them slightly within magnetic fields. Other bacteria can also be vertically motile through changes in their bouyancy.
Wiki User
∙ 13y ago
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What is the whip-like appendage called on some bacteria?
Some bacteria have a whip-like tail called aflagellum. This structure is essential for locomotion, or motility.
Does proteus vulgaris produce h2s?
Yes, it does. It is Indole Production positive, H2S positive, and Motility positive. This can all be seen using SIM agar. Yes, it does. It is Indole Production positive, H2S positive, and Motility positive. This can all be seen using SIM agar.
What are the components of a flagellum?
A whip-like organelle specialized for locomotion. Flagella are found among all three domains of life - bacteria, archaea, and eukaryotes - but the structure of the appendage is different in each of these domains.Bacterial flagellumBacterial flagellumIn bacteria, the filament is composed of the protein flagellin and is a hollow tube 20 nanometers thick. It is helical, and has a sharp bend just outside the outer membrane called the hook which allows the helix to point directly away from the cell. A shaft runs between the hook and the basal body, passing through protein rings in the cell's membranes that act as bearings. Gram-positive (see Gram's stain) organisms have 2 basal body rings, one in the peptidoglycan layer and one in the cell membrane. Gram-negative organisms have 4 rings: L ring associates with the lipopolysaccharides, P ring associates with peptidoglycan layer, M ring is imbedded in the cell membrane, and the S ring is directly attached to the cell membrane. The filament ends with a capping protein.The bacterial flagellum is driven by a rotary engine composed of protein, located at the flagellum's anchor point on the inner cell membrane. The engine is powered by proton motive force, i.e., by the flow of protons (i.e., hydrogen ions) across the bacterial cell membrane due to a concentration gradient set up by the cell's metabolism (in Vibrio species the motor is a sodium ion pump, rather than a proton pump). The rotor transports protons across the membrane, and is turned in the process. The rotor by itself can operate at 6,000 to 17,000 rpm, but with a filament attached usually only reaches 200 to 1000 rpm.The components of the flagellum are capable of self-assembly in which the component proteins associate spontaneously without the aid of enzymes or other factors. Both the basal body and the filament have a hollow core, through which the component proteins of the flagellum are able to move into their respective positions. The filament grows at its tip rather than at the base. The basal body has many traits in common with some types of secretory pore which have a hollow rod-like plug in their centers extending out through the cell membrane, and it is thought that bacterial flagella may have evolved from such pores.Different species of bacteria have different numbers and arrangements of flagella. Monotrichous bacteria have a single flagellum. Lophotrichous bacteria have multiple flagella located at the same spot on the bacteria's surface which act in concert to drive the bacteria in a single direction. Amphitrichous bacteria have a single flagellum each on two opposite ends (only one end's flagellum operates at a time, allowing the bacteria to reverse course rapidly by switching which flagellum is active). Peritrichous bacteria have flagella projecting in all directions.Some species of bacteria (those of Spirochete body form) have a specialized type of flagellum called axial filament that is located in the periplasmic space, the rotation of which causes the entire bacterium to corkscrew through its usually viscous medium.Anticlockwise rotation of monotrichous polar flagella thrusts the cell forward with the flagellum trailing behind. Periodically the direction of rotation is briefly reversed, causing what is known as a tumble, and results in reorientation of the cell. The direction at the end of the tumble state is random. The length of the run state is extended when the bacteria moves through a favorable gradient.Archaeal flagellumThe archaeal flagellum is superficially similar to the bacterial flagellum; in the 1980s they were thought to be homologous on the basis of gross morphology and behavior. Both flagella consist of filaments extending outside of the cell, and rotate to propel the cell. However, discoveries in the 1990s have revealed numerous detailed differences between the archaeal and bacterial flagella; these include:Bacterial flagella are powered by a flow of hydrogen ions (or occasionally sodium ions); archaeal flagella are almost certainly powered by ATP. The torque-generating motor that powers rotation of the archaeal flagellum has not been identified.While bacterial cells often have many flagellar filaments, each of which rotates independently, the archaeal flagellum is composed of a bundle of many filaments that rotate as a single assembly.Bacterial flagella grow by the addition of flagellin subunits at the tip; archaeal flagella grow by the addition of subunits to the base.Bacterial flagella are thicker than archaeal flagella, and the bacterial filament has a large enough hollow tube inside that the flagellin subunits can flow up the inside of the filament and get added at the tip; the archaeal flagellum is too thin to allow this.Many components of bacterial flagella share sequence similarity to components of the type III secretion systems, but the components of bacterial and archaeal flagella share no sequence similarity. Instead, some components of archaeal flagella share sequence and morphological similarity with components of type IV pili, which are assembled through the action of type II secretion systems (the nomenclature of pili and protein secretion systems is not consistent).These differences mean that the bacterial and archaeal flagella are a classic case of biological analogy, or convergent evolution, rather than homology.Eukaryotic flagellumEuglena: a eukaryote with a flagellumThe eukaryotic flagellum, also called a cilium or undulipodium, is completely different from the prokaryote flagella in structure and in evolutionary origin. The only thing that the bacterial, archaeal, and eukaryotic flagella have in common is that they project from the cell and wiggle to produce propulsion.A eukaryotic flagellum is a bundle of nine fused pairs of microtubules doublets surrounding two central single microtubules. The so-called "9+2"" structure is the characteritics of the core of the eukaryotic flugellum called an axoneme. At the base of a eukaryotic flagellum is a basal body or kinetosome, which is the microtubule organizing center for flagellar microtubules and is about 500 nanometers long. Basal bodies are structually identical to centrioles. The flagellum is encased within the cell membrane, so that the interior of the flagellum is accessible to the cell's cytoplasm. Each of the outer 9 doublet microtubules extends a pair of dynein arms (an inner and an outer arm) to the adjacent microtubule; these dynein arms are responsible for flagellar beating, as the force produced by the arms causes the microtubule doublets to slide against each other and the flagellum as a whole to bend. These dynein arms produce force through ATP hydrolysis. The flagellar axoneme also contains radial spokes - polypeptide complexes extending from each of the outer 9 mictrotubule doublets towards the central pair, with the "head" of the spoke facing inwards. The radial spoke is thought to be involved in the regulation of flagellar motion, although its exact function and method of action are not yet understood.In addition to its obvious role in cellular motility, recent research shows that the flagellum may be a vital organelle in sensation and signal transduction across a wide variety of cell types. Intraflagellar transport, the process by which axonemal subunits, transmembrane receptors, and other proteins are moved up and down the length of the flagellum, is essential for proper functioning of the flagellum, in both motility and signal transduction.
What advantage would an animal with jointed legs have?
An animal with jointed legs have greater motility and can run while those without would have a hard time. Take your legs for example. If we did not have knees, we would have a much harder time walking(and moving in general) and instead of the quasi-falling movement we use for walking now, we would have to swing out legs slightly in circles in order to walk. Also, jointed legs allow for a type of "cushion" when animals jump. The bending of legs allows use to carry our weight along with the additional pressure when we jump. A single bone doesn't have to be strong enough as the force is dispersed along several bones and other "shock absorbers".
What does protoSlo do?
ProtoSlo is the brand name of viscous, watery, non-toxic, methyl cellulose solution that's used to slow down protists (unicellular eukaryotic organisms) during light microscopy procedures. Most unicellular protists have motility mechanisms optimized for the normal viscosity of water, so they will be rendered quite motionless if placed on a more viscous medium. Another brand name for this kind of methyl cellulose solution is Detain.
What morphological structure responsible for bacterial motility?
flagellla
What are clusters of bacteria called?
Bacteria that multiply quickly and have no motility form colonies in a cluster. However, so bacteria that have motility do not form clusters.
What microscope used to study motility of bacteria?
phase contrast
What is the structure motility in Amoeba?
pseudopods
What is the structure of motility in paramecium?
cilia
What is the structure of motility in amoeba?
It is pseudopodium
What does a tail of a bacteria is for?
It is called a flagellum.
Why is motility medium semi-solid?
Because it does not inhibit bacteria form "swimming" through the medium.
What media are use to determine motility and growth patterns of bacteria?
SIM test
Is it feasible to determine motility using a side prepared by the Gram Stain techniques?
Bacteria are hard to see if they are not stained, but if you stain them they are dead, so motility can not be determined.
What are the morphological charateristics of bacteria?
Bacteria have a cell wall (not a cellulose cell wall like plants though) and some have a flagellum for movement. The flagellum is like a tail and enables motility. Bacteria also contain circular DNA situated in the cytoplasm. In addition, bacteria have plasmids, which are circular loops of DNA that are useful in genetic engineering. Bacteria also have a cell mebrane and ribosomes. Some bacteria also have a slimy capsule and hair like structures called pili to help them attach to cells.
What is cholera bacterium?
It is a gram negative rod shaped curved bacteria. It has got a flagellum at one end to give motility to the bacteria.
