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CO2 AND RUBISCO. "In the marine environment, CO2 is present in micromolar concentrations, which may be lower than the dissociation constant (Km) for the photosynthetic carbon-fixing enzyme ribulose bisphosphate carboxylase oxygenase (Rubisco). Phytoplankton species that rely on CO2 diffusion to supply photosynthesis may be rate-limited by the CO2 concentration and diffusion to the site of Rubisco in the chloroplast." https://lnkd.in/eXTtntg View in LinkedIn

SUPERSATURATION. "The most striking feature of calcification in the oceans is that it occurs almost exclusively by biogenic processes. Ca2 and CO2 inputs into the oceans occur through weathering of rocks, geothermal activity and hydrothermal seepage. The ocean is in fact supersaturated with Ca2 and CO2. However, spontaneous chemical precipitation is largely absent owing to the high concentrations of inhibitory ions in seawater and the presence of crystal poisons produced by the biota." https://lnkd.in/eXTtntg View in LinkedIn

SUPERSATURATION. "The most striking feature of calcification in the oceans is that it occurs almost exclusively by biogenic processes. Ca2 and CO2 inputs into the oceans occur through weathering of rocks, geothermal activity and hydrothermal seepage. The ocean is in fact supersaturated with Ca2 and CO2. However, spontaneous chemical precipitation is largely absent owing to the high concentrations of inhibitory ions in seawater and the presence of crystal poisons produced by the biota." https://lnkd.in/eXTtntg View in LinkedIn

SUPERSATURATION. "The most striking feature of calcification in the oceans is that it occurs almost exclusively by biogenic processes. Ca2 and CO2 inputs into the oceans occur through weathering of rocks, geothermal activity and hydrothermal seepage. The ocean is in fact supersaturated with Ca2 and CO2. However, spontaneous chemical precipitation is largely absent owing to the high concentrations of inhibitory ions in seawater and the presence of crystal poisons produced by the biota." https://lnkd.in/eXTtntg View in LinkedIn

SATURATION. "There is evidence that calcification can frequently still occur when the external Ca2+ and/or CO3(2-) are so low as to cause undersaturation of the medium with respect to calcite...in the case of celestite and silica, the present surface ocean is well below the saturation value for these 2 minerals, and for silica this has been the case since (at least) soon after the appearance of diatoms in the fossil record...By contrast, the present surface ocean is supersaturated with respect to calcite, although this is forecast to change due to increases in CO2." https://lnkd.in/e2i9eMi View in LinkedIn

SOLUBLE SILICON. "While silica deposition and cell division can occur close to maximal rates at silicon concentrations that are limiting for silicon uptake, diatoms can accumulate soluble silicon between 20 and 400 mmol L(-1), exceeding the solubility for silicon and in some cases enough to synthesize an entire frustule without further silicon input." https://lnkd.in/eXTtntg View in LinkedIn

"CHIRALITY is a predictable result of nucleation on a biochemical substrate since virtually all organic macromolecules are chiral and occur in natural systems as only one enantiomorph. Therefore, a plausible model for the precise nucleation control around the margin of the organic baseplate is that a belt of macromolecular substrate occurs in this position with arrays of potential binding sites for calcium or carbonate ions which promotes nucleation of oriented calcite crystallites." https://lnkd.in/eUUB9pU View in LinkedIn

NUCLEATION. "The presence of a foreign surface can be used to exert even greater control over nucleation because, quite often, the interfacial energy between a crystal nucleus and a solid substrate is lower than that of the crystal in contact with the solution. This is because the molecules in the crystal can form bonds with those in the substrate that are stronger than the bonds of solvation. Because the enthalpic contribution to the free energy comes primarily from chemical bonding, stronger bonds lead to a smaller interfacial free energy." https://lnkd.in/eVX4ANS View in LinkedIn

ORGANIC TEMPLATES. "There is a substantial body of evidence to suggest that proteins and other organic molecules serve as “templates,” providing preferential sites for nucleation and controlling the orientation of the resulting crystals. Many organic-inorganic composites, including the shells of birds’ eggs and mollusks, exhibit a layered structure in which the inorganic component grows at the organic-solution interface." https://lnkd.in/eVX4ANS View in LinkedIn

NUCLEATION. "The first stage of biomineralization is nucleation of a ring of calcite nuclei with alternating orientations. This is a distinctive feature of heterococcoliths with no obvious parallels in any other biomineralization systems and has demonstrably remained constant through more than 200 million years of coccolith evolution...heterococcolith rim nucleation is characterized by a suite of features: alternation of c-axis orientations, control of a-axis orientations, stability through evolutionary history and chirality." https://lnkd.in/eUUB9pU View in LinkedIn