Silicic acid chromatography was employed to determine the distribution of the phosphatides in mouse epidermis undergoing normal growth changes induced by the hair growth cycle. These included epidermis removed 4, 12, and 22 days after plucking of the hair in both sexes of mice. Furthermore, the distribution of phosphatides was determined in mouse epidermis made hyperplastic by three, eighteen, ...

Chitin is a globally abundant polymer widely distributed throughout eukaryotes that has been well characterized in only a few lineages. Diatoms are members of the eukaryotic lineage of stramenopiles. Of the hundreds of diatom genera, two produce long fibers of chitin that extrude through their cell walls of silica. We identify and describe here genes encoding putative chitin synthases in a vari...

A systematic model study on the role(s) of putrescine homologues on silicification is presented and it is proposed that electrostatic forces between additive and silicic acid, and the hydrophobic behaviour of the additives are both important in silicification.

OF the several colorimetric methods which have been described for the estimation of small amounts of silica, probably that of Dienert and Wandenbulche [1923] has met with most favour. The principle of this method is the production of a yellow silicomolybdic acid complex; it was first studied by Schreiner [1903] and Lincoln and Barker [1904]. Winkler [1914] used a similar method for studying the...

Marine diatoms are silica-precipitating microalgae that account for over half of organic carbon burial in marine sediments and thus they play a key role in the global carbon cycle. Their evolutionary expansion during the Cenozoic era (66 Ma to present) has been associated with a superior competitive ability for silicic acid relative to other siliceous plankton such as radiolarians, which evolve...