Related topics: protein · vitamin d

A new strategy for the greener use of calcium carbide

Calcium acetylide was discovered more than 150 years ago. It is a yellowish-white, beige, or gray solid, a compound of calcium and carbon. Calcium acetylide is currently used to produce gaseous acetylene. In industry, it ...

Imaging method reveals a 'symphony of cellular activities'

Within a single cell, thousands of molecules, such as proteins, ions, and other signaling molecules, work together to perform all kinds of functions—absorbing nutrients, storing memories, and differentiating into specific ...

Giant aquatic bacterium is a master of adaptation

The largest freshwater bacterium, Achromatium oxaliferum, is highly flexible in its requirements, as researchers led by the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) have now discovered: It lives ...

From hard to soft: Making sponges from mussel shells

Scientists have discovered a spongy form of calcium carbonate (CaCO3), a material found in limestone, chalk, marble, and the shells of mussels and other shellfish. While most forms of calcium carbonate are hard minerals, ...

To survive asteroid impact, algae learned to hunt

Tiny, seemingly harmless ocean plants survived the darkness of the asteroid strike that killed the dinosaurs by learning a ghoulish behavior—eating other living creatures.

Calcium bursts kill drug-resistant tumor cells

Multidrug resistance (MDR)—a process in which tumors become resistant to multiple medicines—is the main cause of failure of cancer chemotherapy. Tumor cells often acquire MDR by boosting their production of proteins that ...

Researchers probe memory of the Venus flytrap

The carnivorous plant Venus flytrap (Dionaea muscipula) captures and digests small animals and absorbs nutrients with its characteristic insectivorous leaves. Six sensory hairs on the inner surface of each leaf sense a visiting ...

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Calcium (pronounced /ˈkælsiəm/) is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft grey alkaline earth metal, and is the fifth most abundant element by mass in the Earth's crust. Calcium is also the fifth most abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, magnesium, and sulfate.

Calcium is essential for living organisms, particularly in cell physiology, where movement of the calcium ion Ca2+ into and out of the cytoplasm functions as a signal for many cellular processes. As a major material used in mineralization of bones and shells, calcium is the most abundant metal by mass in many animals.

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