90 Sentences With "calcifying" | Random Sentence Generator

Carbonation has a way of calcifying fresh rice and breaking it into little lumpy bits.

Alcohol becomes her solace and she retreats into unchecked anxiety, her insecurities calcifying into agoraphobia.

"Fluoride is meant to strengthen teeth, but it produces more of a calcifying effect," he said.

"The fat lobules lose their blood supply, and they respond by calcifying and turning hard, into a lump," says Dr. Euhus.

"Our results suggest that future ocean acidification and possible effects on marine calcifying organisms will be more severe than during the PETM," Zeebe said.

Research in this vein tends to focus on the similar threats faced by calcifying marine life such as corals, clams, oysters, and sea urchins.

An explosion of jobs in high-growth fields could have unintended consequences when it comes to calcifying diversity gaps and even exacerbating wage inequality.

Ocean acidification poses a major threat to calcifying organisms, such as sea butterflies and mussels, with indications that problems are already showing up in ecosystems.

This has increased ocean surface acidity by 30%, preventing calcifying life forms, including coral, from absorbing the nutrients necessary for them to maintain their structure.

There's no dialogue or much narrative, although there are some tantalizing questions such as why the invaders that are calcifying Semblance look so much like your character.

Often, the approximate nature of regulatory decisions means that rules are imposed by assumption, calcifying into "guidelines" as everyone forgets to ask what they can and cannot do.

These days, travel photos are captured with the understanding that they will be shared on social media in a feed of hundreds of other photos, further calcifying your personal brand.

Drip, drip, drip went her daughter's tears on the old woman's heart, each drop calcifying a little the fibers till at the end of four days the petrifying process was complete.

Halimeda are calcifying organisms, which means they are sensitive to the acidification and warming of the ocean—but how this shift in oceanic conditions has affected their development remains to be seen.

The Houthis have indiscriminately shelled civilian populations in Aden and Taiz, preventing food, water, fuel, and medicine from entering the cities, calcifying regional and sectarian rivalries into hatred that may take decades to undo.

A rumor took hold, calcifying into legend, that his chauffeur would drive the car onto the lot and park — so it would look as if Mr. Grey were somewhere on the premises — and then take a taxi home.

It's been almost five years since the last of the great unlimited data plans died out and left just a few calcifying tendrils of grandfather access for those willing to live the remainder of their days on 23G phones.

Not just positive harm, such as the misidentification of a suspect in a crime, but negative harm, such as calcifying biases in data and business practices in algorithmic form and depriving those affected by the biases of employment or services.

"Even in the event of a rate increase, we doubt the precious metal will lose much ground ahead of the key presidential elections in France in April, coupled with the Washington gridlock that seems to be calcifying," INTL FCStone analyst Edward Meir said.

The legitimization of the group by China ahead of any agreement would provide a significant advantage to the group, both in terms of calcifying the land under their control in Logar, as well as projecting the group as a competent, responsible alternative to the central government.

The Brexit vote, he added, reflects a deep distrust of the benefits of the global economic system among a wide swath of voters in Europe and the United States, and a broadly held view that government institutions — whether in Washington or Brussels — are calcifying and don't work well.

Calcifying organisms generally exhibit larger negative responses from ocean acidification than non‐calcifying organisms across numerous response variables, with the exception of crustaceans, which calcify but don't seem to be negatively affected. This is due, mainly, to the process of marine biogenic calcification, that calcifying organisms utilize.

Chaetocladus is a non-calcifying genus of unicellular green algae known from the Upper Silurian.

It is estimated that the global calcium carbonate production can range from 0.64 to 2 gigatons of carbon per year (Gt C/yr). In the case of a well-known calcifying group, the molluscs, the seawater with the carbonate and calcium ions diffuses through the organism's tissue into calcifying areas next to their shells. Here, the ions combine to form crystals of calcium carbonate in their shells. However, molluscs are only one group of calcifying organisms, and each group has different ways of forming calcium carbonate.

One of the largest potential threats of ocean acidification to marine invertebrates is the corrosive properties of undersaturated waters with respect to calcium carbonate skeletons/shells, and a theoretical inability to calcify under these conditions. Ocean acidification is a lowered pH of ocean waters caused by increased carbon dioxide emissions into the atmosphere, which results in more CO2 dissolving into the ocean. This poses a threat to corals and calcifying macroalgae, two main calcifying groups that occur in reefs, as well as other shelled organisms and the organisms that depend on them. Corals and calcifying macroalgae such as coralline red algae and calcifying green algae are extremely sensitive to ocean acidification because they build their hard structures out of calcium carbonate.

As mentioned above, the molluscs are a well- known group of calcifying organisms. This diverse group contains the slugs, cuttlefish, oysters, limpets, snails, scallops, mussels, clams, octopi, squid, and others. In order for organisms such as oysters and mussels to form calcified shells, they must uptake carbonate and calcium ions into calcifying areas next to their shells. Here they reinforce the protein casing of their shell with calcium carbonate.

The Great Barrier Reef is a biodiversity hotspot, but it is threatened by ocean acidification and its resulting increased temperature and reduced levels of aragonite. Elasmobranchs in the Great Barrier Reef are vulnerable to ocean acidification primarily due to their reliance on the habitat and ocean acidification's destruction of coral reefs. Rare and endemic species, such as the porcupine ray, are at high risk as well. Larval health and settlement of both calcifying and non- calcifying organisms can be harmed by ocean acidification.

The excess carbon sequestered by the ocean results in ocean acidification, which has an especially large impact on the Southern Ocean since this ocean basin naturally has lower calcium carbonate concentrations. The increasing acidity will decrease the calcium carbonate concentrations even more making it difficult for calcifying organisms to develop and survive. The decline of calcifying organisms will have serious repercussions for the rest of the food web in the Southern Ocean, so it is important to quantify how much this ocean is acidifying.

Other species of calcifying larvae have shown reduced growth rates under ocean acidification scenarios. Biofilm, a bioindicator for oceanic conditions, underwent reduced growth rate and altered composition in acidification, possibly affecting larval settlement on the biofilm itself.

Aponeurotic fibroma (also known as "Calcifying aponeurotic fibroma," and "Juvenile aponeurotic fibroma") is characterized by a lesion that usually presents as a painless, solitary, deep fibrous nodule, often adherent to tendon, fascia, or periosteum, on the hands and feet.Freedberg, et al. (2003). Fitzpatrick's Dermatology in General Medicine. (6th ed.).

In addition to the limestone pavement, major landscape types, providing the habitats for the flora and fauna, include limestone heath, dry calcareous grasslands, calcareous (calcifying or petrifying) springs, the intermittent water bodies called turloughs, bogs, cladium fens, lakes, wet grasslands, scrub and light woodland, and neutral, and farm-improved, grasslands.

While ocean absorption of anthropogenic CO2 from the atmosphere acts to decrease climate change, it causes ocean acidification which is believed will have negative consequences for marine ecosystems.Orr, J. C. et al. (2005). Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms. Nature 437, 681-686.

Although red tide is harmful, other beneficial photosynthetic organisms may benefit from increased levels of carbon dioxide. Most importantly, seagrasses will benefit. An experiment done in 2018 concluded that as seagrasses increased their photosynthetic activity, calcifying algae's calcification rates rose. This could be a potential mitigation technique in the face of increasing acidity.

Areas with coastal upwelling such as the west coast of North America have experienced increases in acidification due to more acidic deep water upwelling into the estuary. This may have a detrimental effect on the survival of calcifying organisms because the organisms have a much more difficult time forming and maintaining their calcium carbonate shells.

The accumulation of ions is driven by ion pumps packed within the calcifying epithelium. Calcium ions are obtained from the organism's environment through the gills, gut and epithelium, transported by the haemolymph ("blood") to the calcifying epithelium, and stored as granules within or in-between cells ready to be dissolved and pumped into the extrapallial space when they are required. The organic matrix forms the scaffold that directs crystallization, and the deposition and rate of crystals is also controlled by hormones produced by the mollusc. Because the extrapallial space is supersaturated, the matrix could be thought of as impeding, rather than encouraging, carbonate deposition; although it does act as a nucleating point for the crystals and controls their shape, orientation and polymorph, it also terminates their growth once they reach the necessary size.

These stressors can have damaging effects on these organisms, with some being affected more than others. Calcifying organisms specifically appear to be the most impacted by this changing water composition, as they rely on carbonate availability to survive. Dissolved carbonate concentrations decrease with increasing carbon dioxide and lowered pH in the water. Ecological food webs are also altered by the acidification.

Ediacaran mineralized tubes are often found in carbonates of the stromatolite reefs and thrombolites, i.e. they could live in an environment adverse to the majority of animals. Although they are as hard to classify as most other Ediacaran organisms, they are important in two other ways. First, they are the earliest known calcifying organisms (organisms that built shells from calcium carbonate).

Corallines live in varying depths of water, ranging from periodically exposed intertidal settings to 270 m water depth (around the maximum penetration of light). Some species can tolerate brackish or hypersaline waters, and only one strictly freshwater coralline species exists. (Some species of the morphologically similar, but non-calcifying, Hildenbrandia, however, can survive in freshwater.) A wide range of turbidities and nutrient concentrations can be tolerated.

Calcifying organisms use calcium carbonate to produce shells, skeletons, and tests. The prey base that octopuses prefer (crab, clams, scallops, mussels, etc.) are negatively impacted by ocean acidification, and may decrease in abundance. Shifts in available prey may force a change upon octopus diets to other nonshelled organisms. Because octopuses have hemocyanin as copper-based blood, a small change in pH can reduce oxygen-carrying capacity.

During the Ediacaran period, two main groups of organisms are found in the fossil record: the "Ediacara biota" of soft-bodied organisms, preserved by microbial mats; and calcifying organisms such as Cloudina and Namacalathus, which had a carbonate skeleton. Because both these groups disappear abruptly at the end of the Ediacaran period, , their disappearance cannot simply represent the closure of a preservational window, as had previously been suspected.

Increasing carbon dioxide levels can reduce coral growth rates from 9 to 56%. Other calcifying organisms, such as bivalves and gastropods, experience negative effects due to ocean acidification as well. As a biodiversity hotspot, the many taxa of the Great Barrier Reef are threatened by ocean acidification. Rare and endemic species are in greater danger due to ocean acidification, because they rely upon the Great Barrier Reef more extensively.

A coccolithophore with many coccoliths (plates) formed from calcium carbonate As the pH of marine systems decreases, it causes calcium carbonate (CaCO3) to dissociate to keep in chemical equilibrium. Calcium carbonate is vital to calcifying organisms such as shellfish, corals, and coccolithophores (a type of phytoplankton). Acidification also harms micro-organisms in the environment. These organisms either directly provide humans with a food source or supports an ecosystem important to humans.

The accumulation of ions is driven by ion pumps packed within the calcifying epithelium. The organic matrix forms the scaffold that directs crystallization, and the deposition and rate of crystals is also controlled by hormones produced by the mollusc. The periostracum was probably essential in allowing early molluscs to obtain large size with a single valve. The periostracum is secreted from a groove in the mantle, termed the periostracal groove.

Orr, J.C., Fabry, V.J., Aumont, O., Bopp, L., Doney, S.C., Feely, R.A., Gnanadesikan, A., Gruber, N., Ishida, A., Joos, F. and Key, R.M., 2005. Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms. Nature, 437(7059), pp.681-686. .Hoegh-Guldberg, O., Mumby, P.J., Hooten, A.J., Steneck, R.S., Greenfield, P., Gomez, E., Harvell, C.D., Sale, P.F., Edwards, A.J., Caldeira, K. and Knowlton, N., 2007.

Nature 450, 545–548. However, climate change may affect the biological pump in the future by warming and stratifying the surface ocean. It is believed that this could decrease the supply of nutrients to the euphotic zone, reducing primary production there. Also, changes in the ecological success of calcifying organisms caused by ocean acidification may affect the biological pump by altering the strength of the hard tissues pump.

In combination with other mitigation measures, carbon sinks and removal are crucial for meeting the 2 degree target. The Antarctic Climate and Ecosystems Cooperative Research Centre (ACE-CRC) notes that one third of humankind's annual emissions of are absorbed by the oceans. However, this also leads to ocean acidification, which may harm marine life. Acidification lowers the level of carbonate ions available for calcifying organisms to form their shells.

The threat of acidification includes a decline in commercial fisheries and in the Arctic tourism industry and economy. Commercial fisheries are threatened because acidification harms calcifying organisms which form the base of the Arctic food webs. Pteropods and brittle stars both form the base of the Arctic food webs and are both seriously damaged from acidification. Pteropods shells dissolve with increasing acidification and the brittle stars lose muscle mass when re-growing appendages.

Polymers such as some microporous grades of PMMA and various other acrylates (such as polyhydroxylethylmethacrylate aka PHEMA), coated with calcium hydroxide for adhesion, are also used as alloplastic grafts for their inhibition of infection and their mechanical resilience and biocompatibility. Calcifying marine algae such as Corallina officinalis have a fluorohydroxyapatitic composition whose structure is similar to human bone and offers gradual resorption, thus it is treated and standardized as "FHA (Fluoro-hydroxy-apatitic) biomaterial" alloplastic bone grafts.

Marine biogenic calcification is the process by which marine organisms such as oysters and clams form calcium carbonate. Seawater is full of dissolved compounds, ions and nutrients that organisms can utilize for energy and, in the case of calcification, to build shells and outer structures. Calcifying organisms in the ocean include molluscs, foraminifera, coccolithophores, crustaceans, echinoderms such as sea urchins, and corals. The shells and skeletons produced from calcification have important functions for the physiology and ecology of the organisms that create them.

This process can increase sea surface temperature, decrease aragonite, and lower the pH of the ocean. Calcifying organisms are under risk, due to the resulting lack of aragonite in the water and the decreasing pH. This decreased health of coral reefs, particularly the Great Barrier Reef, can result in reduced biodiversity. Organisms can become stressed due to ocean acidification and the disappearance of healthy coral reefs, such as the Great Barrier Reef, is a loss of habitat for several taxa.

Coral is a calcifying organism, putting it at high risk for decay and slow growth rates as ocean acidification increases. Aragonite, which impacts the ability of coral to take up CaCO3, decreases when pH decreases. Levels of aragonite have decreased by 16% since industrialization, and could be lower in some portions of the Great Barrier Reef because the current allows northern corals to take up more aragonite than the southern corals. Aragonite is predicted to reduce by 0.1 by 2100.

Shells of pteropods dissolve in increasingly acidic conditions caused by increased amounts of atmospheric CO2 Although the natural absorption of by the world's oceans helps mitigate the climatic effects of anthropogenic emissions of , it is believed that the resulting decrease in pH will have negative consequences, primarily for oceanic calcifying organisms. These span the food chain from autotrophs to heterotrophs and include organisms such as coccolithophores, corals, foraminifera, echinoderms, crustaceans and molluscs.National Research Council. Overview of Climate Changes and Illustrative Impacts.

Carbonate ions (CO₃²⁻) are essential in marine calcifying organisms, like plankton and shellfish, as they are required to produce their calcium carbonate (CaCO₃) shells and skeletons. As the ocean acidifies, the increased uptake of CO2 by seawater increases the concentration of hydrogen ions, which lowers the pH of the water. This change in the chemical equilibrium of the inorganic carbon system reduces the concentration of these carbonate ions. This reduces the ability of these organisms to create their shells and skeletons.

Pterapod shell dissolved in seawater adjusted to an ocean chemistry projected for the year 2100 The two polymorphs of calcium carbonate that are produced by marine organisms are aragonite and calcite. These are the materials that makes up most of the shells and skeletons of these calcifying organisms. Aragonite, for example, makes up nearly all mollusc shells, as well as the exoskeleton of corals. The formation of these materials is dependent on the saturation state of CaCO3 in ocean water.

Rugose corals built their skeletons of calcite and have a different symmetry from that of the scleractinian corals, whose skeletons are aragonite. However, there are some unusual examples of well-preserved aragonitic rugose corals in the Late Permian. In addition, calcite has been reported in the initial post-larval calcification in a few scleractinian corals. Nevertheless, scleractinian corals (which arose in the middle Triassic) may have arisen from a non-calcifying ancestor independent of the rugosan corals (which disappeared in the late Permian).

The effects on the calcifying organisms at the base of the food webs could potentially destroy fisheries. The value of fish caught from US commercial fisheries in 2007 was valued at $3.8 billion and of that 73% was derived from calcifiers and their direct predators. Other organisms are directly harmed as a result of acidification. For example, decrease in the growth of marine calcifiers such as the American lobster, ocean quahog, and scallops means there is less shellfish meat available for sale and consumption.

Echinoderms, of the phylum Echinodermata, include sea creatures such as sea stars, sea urchins, sand dollars, crinoids, sea cucumbers and brittle stars. This group of organisms is known for their radial symmetry and they mostly use the intracellular calcifying strategy, keeping their calcified structures inside their bodies. They form large vesicles from the fusing of their cell membranes and inside these vesicles is where the calcified crystals are formed. The mineral is only exposed to the environment once those cell membranes are degraded, and therefore serve as a sort of skeleton.

Weathering is the natural process in which rocks are broken down and dissolved on the land surface. When silicate or carbonate minerals dissolve in rainwater, carbon dioxide is drawn into the solution from the atmosphere through the reactions below (Eq.1&2) to form bicarbonate ions: Eq.1 Forsterite: Mg2SiO4 \+ 4CO2 \+ 4H2O → 2Mg2+ \+ 4HCO3− \+ H4SiO4 Eq.2 Calcite : CaCO3 \+ CO2 \+ H2O → Ca2+ \+ 2HCO3− Rainwater and bicarbonate ions eventually end up in the ocean, where they are formed into carbonate minerals by calcifying organisms (Eq.3), which then sinks out of the surface ocean.

Waters which are saturated in CaCO₃ are favorable to precipitation and formation of CaCO₃ shells and skeletons, but waters which are undersaturated are corrosive to CaCO₃ shells. In the absence of protective mechanisms, dissolution of calcium carbonate will occur. As colder arctic water absorbs more CO₂, the concentration of CO₃²⁻ is reduced, therefore the saturation of calcium carbonate is lower in high-latitude oceans than it is in tropical or temperate oceans. The undersaturation of CaCO3 causes the shells of calcifying organisms to dissolve, which can have devastating consequences to the ecosystem.

Temperature has a strong effect on the solubility product constants for both calcite and aragonite, with an approximately 20% decrease in K’sp from 0 to 25 °C. The lower solubility constants for calcite and aragonite with elevated temperature have a positive impact on calcium carbonate precipitation and deposition, making it easier for calcifying organisms to produce shells in water with lower solubility of calcium carbonate. Temperature can also influence the calcite:aragonite ratios, as aragonite precipitation rates are more strongly tied to temperature, with aragonite precipitation dominating above 6 °C.

Recent studies show that climate change has direct and indirect impacts on Coccolithophore distribution and productivity. They will inevitably be affected by the increasing temperatures and thermal stratification of the top layer of the ocean, since these are prime controls on their ecology, although it is not clear whether global warming would result in net increase or decrease of coccolithophores. As they are calcifying organisms, it has been suggested that ocean acidification due to increasing carbon dioxide could severely affect coccolithophores. Recent CO2 increases have seen a sharp increase in the population of coccolithophores.

In January, he pulled a muscle in his thigh and missed a week's worth of games. 43 games into the season, after totalling a career-high 40 points, Brickley was sidelined again when doctors discovered that a muscle in his right leg was calcifying, a condition known as myositis ossificans. Despite the injury and extended time out of action, Brickley was allowed to briefly play in Game 3 of the Stanley Cup Finals by Milbury. Brickley had leg surgery on July 17, 1990 and missed all of training camp.

However it is achieved, kleptoplasty is an important strategy for many genera of Placobranchacea. One species of Elysia feeds on a seasonally-calcifying alga. Because it is unable to penetrate the calcified cell walls, the animal can only feed for part of the year, relying on the ingested chloroplasts to survive whilst the foodstuff is calcified, until later in the season when the calcification is lost and the grazing can continue. Sacoglossans can also use anti-herbivory compounds produced by their algal foodstuffs to deter their own would-be predators, in a process termed kleptochemistry.

The sinking pH of ocean waters makes it difficult for these shelled creatures to produce enough calcium carbonate to build and maintain their skeletal structures. Echinoderms, such as sea stars and sea urchins, and mollusks, including squid and clams, as well as many other species are also at risk because of thinning shells and weakened skeletal structures. By targeting calcifying organisms, ocean acidification threatens the health of reef ecosystems as a whole. Ocean acidification from increasing level of atmospheric CO2 represents a major global threat to coral reefs, and in many regions acidification is exacerbated by local smaller-scale disturbances such as overfishing.

The carbon cycle then becomes disrupted and as a result there is a reduction in the concentration of carbonate ions in the seawater. Marine calcification is now inversely affected which impacts calcifying organisms such as corals as it now becomes harder to build and form their calcium carbonate structures. Without a supportive skeleton, corals will naturally be more frail and easily damaged during storm surges, while the rate of growth and recovery are both slowed. The corals also become weaker, and more susceptible to disease which significantly takes a toll on the resilience of the reefs.

This net decrease in the amount of carbonate ions available may make it more difficult for marine calcifying organisms, such as coral and some plankton, to form biogenic calcium carbonate, and such structures become vulnerable to dissolution. Ongoing acidification of the oceans may threaten future food chains linked with the oceans. As members of the InterAcademy Panel, 105 science academies have issued a statement on ocean acidification recommending that by 2050, global emissions be reduced by at least 50% compared to the 1990 level., Secretariat: TWAS (the Academy of Sciences for the Developing World), Trieste, Italy.

Since they harbour an aragonitic shell, they could be very sensitive to ocean acidification driven by the increase of anthropogenic CO₂ emissions. Laboratory tests showed that calcification exhibits a 28% decrease of the pH value of the Arctic ocean expected for the year 2100, compared to the present pH value. This 28% decline of calcification in the lower pH condition is within the range reported for other calcifying organisms such as corals. In contrast with sea urchin and bivalve larvae, corals and marine shrimps are more severely impacted by ocean acidification after settlement, while they developed into the polyp stage.

Creed and Lithia, within their respective hosts, briefly do battle, but the effort on Lithia's part breaks a seal containing their physical forms, allowing the two Minerans to return to them. The group escape Mysticete with Lithia, who explains that in an effort to stop the warring on Minera, Creed, Lithia and her sister Fluora created Gardenia, a xerom capable of remotely absorbing Spirias. Though intended to quell violent thoughts in the population, Gardenia went berserk when activated and absorbed every Spiria on Minera, calcifying the planet.Lithia: Creed, too, once desired peace, although the thing he created in that service was an abomination.

This reaction structure is representative of general silicate weathering of calcium silicate minerals. The chemical pathway is as follows: : 2CO2 + H2O + CaSiO3 -> Ca^2+ + 2HCO3- + SiO2 River runoff carries these products to the ocean, where marine calcifying organisms use Ca2+ and HCO3− to build their shells and skeletons, a process called carbonate precipitation: : Ca^2+ + 2HCO3- -> CaCO3 + CO2 + H2O Two molecules of CO2 are required for silicate rock weathering; marine calcification releases one molecule back to the atmosphere. The calcium carbonate (CaCO3) contained in shells and skeletons sinks after the marine organism dies and is deposited on the ocean floor.

In vitro calcification models have been used in medical implant development to evaluate the calcification potential of the medical device or tissue. They can be considered a subfamily of the bioreactors that have been used in the field of tissue engineering for tissue culture and growth. These calcification bioreactors are designed to mimic and maintain the mechano-chemical environment that the tissue encounters in vivo with a view to generating the pathological environment that would favor calcium deposition. Parameters including medium flow, pH, temperature and supersaturation of the calcifying solution used in the bioreactor are maintained and closely monitored.

Corals are an obvious group of calcifying organisms, a group that easily comes to mind when one thinks of tropical oceans, scuba diving, and of course the Great Barrier Reef off the coast of Australia. However, this group only accounts for about 10% of the global production of calcium carbonate. Corals undergo extracellular calcification and first develop an organic matrix and skeleton on top of which they will form their calcite structures. Coral reefs uptake calcium and carbonate from the water to form calcium carbonate via the following chemical reaction: 2HCO3 \+ Ca2+ → CaCO3 \+ CO2 \+ H2O Dissolved inorganic carbon (DIC) from the seawater is absorbed and transferred to the coral skeleton.

Another challenge for Antarctic krill, as well as many calcifying organisms (corals, bivalve mussels, snails etc.), is the acidification of the oceans caused by increasing levels of carbon dioxide. Krill exoskeleton contains carbonate, which is susceptible to dissolution under low pH conditions. It has already been shown that increased carbon dioxide can disrupt the development of krill eggs and even prevent the juvenile krill from hatching, leading to future geographically widespread decreases in krill hatching success. The further effects of ocean acidification on the krill life cycle however remains unclear but scientists fear that it could significantly impact on its distribution, abundance and survival.

The rate at which these shells form is greatly influenced by physical and chemical characteristics of the water in which these organisms live. Estuaries are dynamic habitats which expose their inhabitants to a wide array of rapidly changing physical conditions, exaggerating the differences in physical and chemical properties of the water. Estuaries have large variation in salinity, ranging from entirely fresh water upstream to fully marine water at the ocean boundary. Estuarine systems also experience daily, tidal and seasonal swings in temperature, which affect many of the chemical characteristics of the water and in turn affect the metabolic and calcifying processes of shell-producing organisms.

However, concentrating tourism activities via offshore platforms has been shown to limit the spread of coral disease by tourists. Greenhouse gas emissions present a broader threat through sea temperature rise and sea level rise, though corals adapt their calcifying fluids to changes in seawater pH and carbonate levels and are not directly threatened by ocean acidification. Volcanic and manmade aerosol pollution can modulate regional sea surface temperatures. In 2011, two researchers suggested that "extant marine invertebrates face the same synergistic effects of multiple stressors" that occurred during the end-Permian extinction, and that genera "with poorly buffered respiratory physiology and calcareous shells", such as corals, were particularly vulnerable.

Most marine species with shells (mollusks, echinoderms, corals, coccolithophores, foraminiferans, calcifying algae, etc.) experience increased dissolution and increasing energetic costs of maintaining and growing these structures in this basic environment. However, living in the middle to lower intertidal zone and shallow waters, A. punctata naturally faces fluctuations in pH and has been observed to have no decrease in calcification of new shell material when exposed to acidic environments similar to those of having increased dissolved carbon dioxide. Although, they do undergo increased metabolic rate in low pH environments which is attributed to the maintenance of calcium carbonate and aragonite structures in waters depleted of these materials.

Acidification may also have played a role in the extinction of the calcifying foraminifera, and the higher temperatures would have increased metabolic rates, thus demanding a higher food supply. Such a higher food supply might not have materialized because warming and increased ocean stratification might have led to declining productivity and/or increased remineralization of organic matter in the water column, before it reached the benthic foraminifera on the sea floor (). The only factor global in extent was an increase in temperature. Regional extinctions in the North Atlantic can be attributed to increased deep-sea anoxia, which could be due to the slowdown of overturning ocean currents, or the release and rapid oxidation of large amounts of methane.

Temperature and salinity affect the carbonate balance of the water, influencing carbonate equilibrium, calcium carbonate solubility and the saturation states of calcite and aragonite. The tidal influences and shallow water of estuaries mean that estuarine organisms experience wide variations in temperature, salinity and other aspects of water chemistry; these fluctuations make the estuarine habitat ideal for studies on the influence of changing physical and chemical conditions on processes such as shell deposition. Changing conditions in estuaries and coastal regions are especially relevant to human interests, because about 50% of global calcification and 90% of fish catch occurs in these locations. A substantial proportion of larger marine calcifying organisms are molluscs: bivalves, gastropods and chitons.

Shell growth and calcification rate are the cumulative outcome of the impacts of temperature and salinity on water chemistry and organismal processes such as metabolism and respiration. It has been established that temperature and salinity influence the balance of the carbonate equilibrium, the solubility and saturation state of calcite and aragonite, as well as the amount of magnesium that gets incorporated into the mineral matrix of the shell. All of these factors combine to produce net calcification rates that are observed under different physical and environmental conditions. Organisms from many phyla produce calcium carbonate skeletons, so organismal processes vary widely, but the effect of physical conditions on water chemistry impacts all calcifying organisms.

Reefs off Vanatinai in the Louisiade Archipelago Ancient reefs buried within stratigraphic sections are of considerable interest to geologists because they provide paleo-environmental information about the location in Earth's history. In addition, reef structures within a sequence of sedimentary rocks provide a discontinuity which may serve as a trap or conduit for fossil fuels or mineralizing fluids to form petroleum or ore deposits. Corals, including some major extinct groups Rugosa and Tabulata, have been important reef builders through much of the Phanerozoic since the Ordovician Period. However, other organism groups, such as calcifying algae, especially members of the red algae Rhodophyta, and molluscs (especially the rudist bivalves during the Cretaceous Period) have created massive structures at various times.

This is the origin of both marine and terrestrial limestone. Calcium precipitates into calcium carbonate according to the following equation: Ca2+ \+ 2HCO3− → CO2\+ H2O + CaCO3 The relationship between dissolved calcium and calcium carbonate is affected greatly by the levels of carbon dioxide (CO2) in the atmosphere. Increased carbon dioxide leads to more bicarbonate in the ocean according to the following equation: CO2 \+ CO32− \+ H2O → 2HCO3− With ocean acidification, inputs of carbon dioxide promote the dissolution of calcium carbonate and harm marine organisms dependent on their protective calcite or aragonite shells.deposition of calcifying organisms/shells on the ocean floor The solubility of calcium carbonate increases with pressure and carbon dioxide and decreases with temperature.

Ultramicrobacteria are commonly confused with ultramicrocells, the latter of which are the dormant, stress-resistant forms of larger cells that form under starvation conditions (ie. these larger cells downregulate their metabolism, stop growing and stabilize their DNA to create ultramicrocells that remain viable for years) whereas the small size of ultramicrobacteria is not a starvation response and is consistent even under nutrient-rich conditions. The term "nanobacteria" is sometimes used synonymously with ultramicrobacteria in the scientific literature, but ultramicrobacteria are distinct from the purported nanobacteria or "calcifying nanoparticles", which were proposed to be living organisms that were 0.1 μm in diameter. These structures are now thought to be non-living, and likely precipitated particles of inorganic material.

Food availability can alter shell growth patterns, as can chemical cues from predators, which cause clams, snails and oysters to produce thicker shells. There are costs to producing thicker shells as protection, including the energetic expense of calcification, limits on somatic growth, and reduced growth rates in terms of shell length. In order to minimize the significant energetic expense of shell formation, several calcifying species reduce shell production by producing porous shells or spines and ridges as more economical forms of predator defense. Temperature and salinity also affect shell growth by altering organismal processes, including metabolism and shell magnesium (Mg) incorporation, as well as water chemistry in terms of calcium carbonate solubility, CaCO3 saturation states, ion-pairing, alkalinity and carbonate equilibrium.

The tumours commonly appear with an asymptomatic "slow-growing, painless, solid subcutaneous or intradermal nodules with a normal margin" (Obaidat, Alsaad, and Ghazarian, 2007) and make up for less than one percent of all primary skin tumours. Commonly appearing in the limbs and body, these asymmetrical tumours range from two millimetres to more than three centimetres. MCS is one of the rarest subtypes of tumours and usually requires aggressive surgery to terminate. Despite accounting for only a small number of tumours recorded each year, malignant mixed tumours are easily confused with other skin conditions (such as epidermal cyst, pilar cyst, calcifying epithelioma, or a solitary trichoepithelioma (Tural, Selçukbiricik, Günver, Karışmaz, and Serdengecti, 2013)) and have high potential for recurrence after surgical excision.

Sex hormones are thought to be linked to this process because of the spatial relationship of chondroblastoma with the growth plate and its typical occurrence before growth plate fusion. Both Indian Hedgehog/Parathyroid Hormone-related Protein (IHh/PtHrP) and fibroblast growth factor (FGF) signaling pathways, important for development of the epiphyseal growth plate, are active in chondroblastoma leading to greater proliferation among the cells in the proliferating/pre-hypertrophic zone (cellular-rich area) versus the hypertrophic/calcifying zone (matrix-rich area). These findings suggest that chondroblastoma is derived from a mesenchymal cell undergoing chondrogenesis via active growth-plate signaling pathways (see Endochondral ossification). The highly heterogeneous nature of the tumor makes classification particularly difficult especially considering the origins of chondroblastoma.

Some Precambrian (Ediacaran) organisms produced tough but non-mineralized outer shells, while others, such as Cloudina, had a calcified exoskeleton, but mineralized skeletons did not become common until the beginning of the Cambrian period, with the rise of the "small shelly fauna". Just after the base of the Cambrian, these miniature fossils become diverse and abundant – this abruptness may be an illusion, since the chemical conditions which preserved the small shellies appeared at the same time. Most other shell-forming organisms appear during the Cambrian period, with the Bryozoans being the only calcifying phylum to appear later, in the Ordovician. The sudden appearance of shells has been linked to a change in ocean chemistry which made the calcium compounds of which the shells are constructed stable enough to be precipitated into a shell.

The ancestor of the Sacoglossa is presumed to have fed on a now-extinct calcifying green alga in the Udoteaceae. The first fossil evidence of the group comes from bivalved shells dating to the Eocene, and further bivalved shells are known from later geological periods, although the thin nature of the shells and their high- erosion habitat usually make for poor preservation. The corresponding fossil record of algae points to an origin of the group deeper in time, perhaps as early as the Jurassic or Cretaceous. The loss of the shell, which was apparently a single evolutionary event, opened up a new ecological avenue for the clade, as the chloroplasts of the green algae on which they fed could now be retained and used as functioning chloroplasts, which could generate energy by photosynthesis.

Most pregnancy in females occurs in the summer and the autumn, and pre-ovulatory periods in females occurred in the winter. in males calcifying claspers were observed during the summer, autumn, and winter. Going along with this pattern in males in females, there is an annual reproductive cycle with a mating season during the spring and a pregnancy and birth season during the summer and the autumn. There is a high energy requirement during the courtship and mating process, there may be bite marks observed in sexually mature female and male dorsal regions during the mating period (Rolim 2016). Life Span/Longevity As stated earlier, not much is known about their life cycle, but what is known is they have a very long surviving capacity and a low natural mortality rate (Marinsek 2017).

A study in 2008 examining a sediment core from the North Atlantic found that while the species composition of coccolithophorids has remained unchanged for the industrial period 1780 to 2004, the calcification of coccoliths has increased by up to 40% during the same time. A 2010 study from Stony Brook University suggested that while some areas are overharvested and other fishing grounds are being restored, because of ocean acidification it may be impossible to bring back many previous shellfish populations. While the full ecological consequences of these changes in calcification are still uncertain, it appears likely that many calcifying species will be adversely affected. When exposed in experiments to pH reduced by 0.2 to 0.4, larvae of a temperate brittlestar, a relative of the common sea star, fewer than 0.1 percent survived more than eight days.

As the shells dissolve, the organisms struggle to maintain proper health, which can lead to mass mortality. The loss of many of these species can lead to intense consequences on the marine food web in the Arctic Ocean, as many of these marine calcifying organisms are keystone species. Laboratory experiments on various marine biota in an elevated CO₂ environment show that changes in aragonite saturation cause substantial changes in overall calcification rates for many species of marine organisms, including coccolithophore, foraminifera, pteropods, mussels, and clams. Although the undersaturation of arctic water has been proven to have an effect on the ability of organisms to precipitate their shells, recent studies have shown that the calcification rate of calcifiers, such as corals, coccolithophores, foraminiferans and bivalves, decrease with increasing pCO₂, even in seawater supersaturated with respect to CaCO₃.

Bivalve clams show higher growth rates and produce thicker shells, more spines, and more shell ornamentation at warmer, low latitude locations, again highlighting the enhancement of calcification as a result of warmer water and the corresponding chemical changes. The short-term changes in calcification rate and shell growth described by the aforementioned studies are based on experimental temperature elevation or latitudinal thermal gradients, but long- term temperature trends can also affect shell growth. Sclerochronology can reconstruct historical temperature data from growth increments in shells of many calcifying organisms based on differential growth rates at different temperatures. The visible markers for these growth increments are similar to growth rings, and are also present in fossil shells, enabling researchers to establish that clams such as Phacosoma balticum and Ruditapes philippinarum grew the fastest during times of warmer climate.