In a demonstration, Schmidt's team managed to capture, transport, and release a single "immotile" live sperm cell in a fluidic bath, an environment that closely resembles an actual physiological system.
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A Dictionary of Biology , 2004, accessed 6 April 2010. Immotile cilia (called primary cilia) communicate signals from the environment or from other cells.
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Necrospermia (or necrozoospermia) is a condition in which there is a low percentage of live and a very high percentage of immotile spermatozoa in semen.World Health Organization (WHO) Laboratory Manual for the Examination and Processing of Human Semen, 5th Edition, 2010 It can be diagnosed via a semen analysis with vitality staining performed to determine whether the sperm are dead or alive and immotile.
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Daughter cells can develop into flagellated cells or remain non-motile, depending on environmental conditions. Additionally, vegetative cells whether flagellate or immotile are anchored to the thecal wall by four microtubule contact points.
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SPATA16 knockout mice are completely infertile, and it is characterized by spermatogenesis arrest and azoospermia. This is where the differentiation process is obstructed during spermatogenesis and creates immotile sperm. In contrast, infertility caused by SPATA16 mutations in male humans develop spermatozoa that are motile, but their sperm exhibit head and acrosome abnormalities.
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In the mouse embryo, cilia are used to direct the flow of extracellular fluid. This leftward movement is used by the mouse embryo to generate left-right asymmetry across the midline of the embryo. Central cilia coordinate their rotational beating while the immotile cilia on the sides sense the direction of the flow.
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For example, the intromittent organ is not present in male alates, and the sperm is either immotile or aflagellate. However, Mastotermitidae termites have multiflagellate sperm with limited motility. The genitals in females are also simplified. Unlike in other termites, Mastotermitidae females have an ovipositor, a feature strikingly similar to that in female cockroaches.
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The tail of the sperm is the driving force for the microtube. The second type, the helical spermbot, is a small helix structure which captures and transports single immotile sperm cells. In this case, a rotating magnetic field drives the helix in a screw-like motion. Both kinds of spermbots can be guided by weak magnetic fields.
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The radial spoke is known to play a role in the mechanical movement of the flagellum/cilium. For example, mutant organisms lacking properly functioning radial spokes have flagella and cilia that are immotile. Radial spokes also influence the cilium "waveform"; that is, the exact bending pattern the cilium repeats. How the radial spoke carries out this function is poorly understood.
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Fig 3: Ventral view of the head of the adult female Ceratothoa oestroides. Fig 4: Dorsal view of the head of the adult female Ceratothoa oestroides. Sexual differentiation occurs only after young leave the brood pouch. As free swimming manca (infective stage), the parasite will seek and attach to an appropriate host, and will then moult, losing the swimming setae and becoming immotile.
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The second pair of cephalic appendages in free-living copepods is usually the main time-averaged source of propulsion, beating like oars to pull the animal through the water. However, different groups have different modes of feeding and locomotion, ranging from almost immotile for several minutes (e.g. some harpacticoid copepods) to intermittent motion (e.g., some cyclopoid copepods) and continuous displacements with some escape reactions (e.g.
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The ookinete is a motile cell, capable of invading other organs of the mosquito. It traverses the peritrophic membrane of the mosquito midgut and crosses the midgut epithelium. Once through the epithelium, the ookinete enters the basal lamina, and settles to an immotile oocyst. For several days, the oocyst undergoes 10 to 11 rounds of cell division to create a syncytial cell (sporoblast) containing thousands of nuclei.
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Asthenozoospermia (or asthenospermia) is the medical term for reduced sperm motility. Complete asthenozoospermia, that is, 100% immotile spermatozoa in the ejaculate, is reported at a frequency of 1 of 5000 men. Causes of complete asthenozoospermia include metabolic deficiencies, ultrastructural abnormalities of the sperm flagellum (see Primary ciliary dyskinesia) and necrozoospermia. It decreases the sperm quality and is therefore one of the major causes of infertility or reduced fertility in men.
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This gene encodes a member of the dynein heavy chain family. It is a microtubule-dependent motor ATPase and has been reported to be involved in the movement of respiratory cilia. Mutations in this gene have been implicated in causing primary ciliary dyskinesia (PCD, formerly called 'immotile cilia syndrome') and Kartagener syndrome (PCD with situs inversus totalis). Males with PCD are not sterile, but are infertile due to lack of sperm motility.
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In addition, Vampirococcus specifically preys upon various species within the bacterial genus, Chromatium, a freshwater purple sulfur bacteria. Because Chromatium is a primary producer as a phototroph, it has been suggested that Vampirococcus could be considered a primary consumer as a predator of photosynthetic bacteria. There is some disagreement in the scientific community regarding Vampirococcus's motility. Many papers have stated that this specific predatory prokaryote does not have cilia or flagella, rendering the prokaryote immotile.
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The eggs are fertilised inside the female, though how the sperm enter the female is unclear since the sperm of this, and other related species, are apparently immotile. The length of gestation depends on the temperature of the water – the cooler the water, the longer it takes. The female provides nutrition directly, her internal organs and muscles degrading throughout the gestation. This gives the juveniles a headstart, before they begin feeding on intertidal algae.
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When in the immotile cyst stage, the C. nivalis cells must depend on the flow of meltwater to move it by chance to a favourable area. The temperatures in which this species can survive in ranges from below 0 °C to just above 20 °C. Growth is slow when temperatures are below 5 °C. At 5-15 °C the growth of C. nivalis cells can outperform the growth of C. reinhardtii cells.
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It also may play a role in protecting the algal cells from desiccation during the freeze-thaw cycle alternations during seasonal changes. The spherical immotile red cysts range from 35-40 µm in diameter. The cell contains one central chloroplast that has a naked pyrenoid, ribosomes, starch grains, and numerous small grana stacks composed of 3-7 thylakoids within it.Holzinger, A.; Lutz, C. (2006). “Algae and UV irradiation: Effects on ultrastructure and related metabolic functions”.
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Cell division in Tetraspora species has been described. It is noted that prior to mitosis beginning, cells become immotile and the basal bodies located at the surface of cells start to retreat in. This causes the preprophase nucleus to migrate toward retreating basal body complex, around which microtubules start to gather. The basal body complex arranges itself to be closely associated with one pole of the cell, creating a mitotic spindle known as open polar fenestrae.
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These gas vesicles have only been produced in the presence of hydrogen and carbon dioxide, likely acting as a response to a hydrogen gradient. M. barkeris chromosome is large and circular, derived from its remarkable ability to metabolize a variety of different carbon molecules. This offers the species an advantage as though it is immotile, it can adapt to its environment depending on the energy sources available. M. barkeris circular plasmid consists of about twenty genes.
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C. fasciculata is found in two morphologically different life cycle stages - the free swimming choanomastigote form, which has a long external flagellum for motility, and the attached, immotile, amastigote form in the mosquito gut. Amastigotes excreted in the faeces contaminate the mosquito habitat; contamination of flowers during nectar feeding is common. Transmission of C fasciculata primarily occurs when amastigotes, washed into standing water, are ingested by mosquito larvae. The amastigotes are typically found in the rectum of a larva.
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The sperm are transferred from the pollen through the pollen tube to the ovule. Pollen tube growth Unlike animal sperm which is motile, plant sperm is immotile and relies on the pollen tube to carry it to the ovule where the sperm is released. The pollen tube penetrates the stigma and elongates through the extracellular matrix of the style before reaching the ovary. Then near the receptacle, it breaks through the ovule through the micropyle (an opening in the ovule wall) and the pollen tube "bursts" into the embryo sac, releasing sperm.
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Although ciliopathies are usually considered to involve proteins that localize to motile and/or immotile (primary) cilia or centrosomes, it is possible for ciliopathies to be associated with unexpected proteins such as XPNPEP3, which localizes to mitochondria but is believed to affect ciliary function through proteolytic cleavage of ciliary proteins. Significant advances in understanding the importance of cilia were made in the mid-1990s. However, the physiological role that this organelle plays in most tissues remains elusive. Additional studies of how ciliary dysfunction can lead to such severe disease and developmental pathologies is still a subject of current research.
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However, the plastids are very different from red algal plastids: phycobiliproteins are present but only in the thylakoid lumen and are present only as phycoerythrin or phycocyanin. In the case of Rhodomonas, the crystal structure has been determined to 1.63Å; and it has been shown that the alpha subunit bears no relation to any other known phycobiliprotein. A few cryptomonads, such as Cryptomonas, can form palmelloid stages, but readily escape the surrounding mucus to become free-living flagellates again. Some Cryptomonas species may also form immotile microbial cysts—resting stages with rigid cell walls to survive unfavorable conditions.
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However, the plastids are very different from red algal plastids: phycobiliproteins are present but only in the thylakoid lumen and are present only as phycoerythrin or phycocyanin. In the case of "Rhodomonas" the crystal structure has been determined to 1.63Å; and it has been shown that the alpha subunit bears no relation to any other known phycobiliprotein. A few cryptophytes, such as Cryptomonas, can form palmelloid stages, but readily escape the surrounding mucus to become free-living flagellates again. Some Cryptomonas species may also form immotile microbial cysts–resting stages with rigid cell walls to survive unfavorable conditions.
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Septoria is present in many parts of the world, but has only become prevalent in the marijuana industry with the movement towards legalization. Ranging from the Emerald Triangle in California, to the cold winds of the east coast, Septoria is becoming an increasing nuisance for cannabis growers. Like most Septoria species they require moist and humid conditions to germinate, because of their conidia being immotile, and survive during the off-season by overwintering on dead and decaying organic matter. The disease moves to other parts of the plant during periods of rain or heavy wind, which enable the dispersal of ascospores (primary cycle) and conidia (secondary cycle) to roam and infect other vegetative tissue.
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Primary ciliary dyskinesia (PCD), is a rare, ciliopathic, autosomal recessive genetic disorder that causes defects in the action of cilia lining the respiratory tract (lower and upper, sinuses, Eustachian tube, middle ear), fallopian tube, and flagellum of sperm cells. The phrase "immotile ciliary syndrome" is no longer favored as the cilia do have movement, but are merely inefficient or unsynchronized. Respiratory epithelial motile cilia, which resemble microscopic "hairs" (although structurally and biologically unrelated to hair), are complex organelles that beat synchronously in the respiratory tract, moving mucus toward the throat. Normally, cilia beat 7 to 22 times per second, and any impairment can result in poor mucociliary clearance, with subsequent upper and lower respiratory infection.
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The few immotiles constantly vie with each other for territories and resources, and by the time of the story, the strongest uses the technology gleaned by analysis of the human's wormhole-generation techniques to destroy all the other Prime immotiles and thus become the only one remaining Prime: MorningLightMountain. Primes had previously colonised the solar system referred to as Dyson Beta using slower-than-light starships and had committed genocide against its native inhabitants in the process. Disconnected from their originating immotile groupings, and provided with novel biological forms, Beta's Primes started to routinely alter themselves through genetic manipulation and mechanical augmentation. This was an anathema to the Alpha Primes, who referred to them as AlienPrimes.
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Early 2000s findings in genetic research have suggested that many genetic disorders, both genetic syndromes and genetic diseases, that were not previously related in the medical literature, may be, in fact, highly related in the root cause of the widely varying set of medical symptoms that are clinically visible in the disorder. These have been grouped as an emerging class of diseases called ciliopathies. The underlying cause may be a dysfunctional molecular mechanism in the primary/immotile cilia, organelles which are present in many diverse cellular types throughout the human body. Cilia defects adversely affect numerous critical signaling pathways essential to embryonic development and adult physiology, and thus offer a plausible hypothesis for the often multi-symptom nature of diverse ciliopathies.
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Many land mammals, for example rats and hamsters, have an arrangement of cranial (of the skull) vibrissae that includes the supraorbital (above the eyes), genal (of the cheeks), and mystacial (where a moustache would be) vibrissae, as well as mandibular (of the jaw) vibrissae under the snout. These groups, all of which are visible in the accompanying image of the Patagonian fox, are well conserved across land mammals though anatomical and functional details vary with the animal's lifestyle. Mystacial vibrissae are generally described as being further divided into two sub-groups: the large macrovibrissae that protrude to the sides and the small microvibrissae below the nostrils that mostly point downwards. Most simply described, macrovibrissae are large, motile and used for spatial sensing, whereas microvibrissae are small, immotile and used for object identification.
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PKD results from defects in the primary cilium, an immotile, hair-like cellular organelle present on the surface of most cells in the body, anchored in the cell body by the basal body. In the kidney, primary cilia have been found to be present on most cells of the nephron, projecting from the apical surface of the renal epithelium into the tubule lumen. The cilia were believed to bend in the urine flow, leading to changes in signalling, however this has since been shown to be an experimental error (the bending of cilia was an artifact of focal plane compensation, and also the actual effect on micturition by severe hypertension and cardiac arrest) and that bending of cilia does not contribute to alterations in Ca flux. While it is not known how defects in the primary cilium lead to cyst development, it is thought to possibly be related to disruption of one of the many signaling pathways regulated by the primary cilium, including intracellular calcium, Wnt/β-catenin, cyclic adenosine monophosphate (cAMP), or planar cell polarity (PCP).
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