Biological Role and Precautions
Magnesium and calcium are ubiquitous and essential to all known living organisms. They are involved in more than one role, with, for example, magnesium or calcium ion pumps playing a role in some cellular processes, magnesium functioning as the active center in some enzymes, and calcium salts taking a structural role, most notably in bones.
Strontium plays an important role in marine aquatic life, especially hard corals, which use strontium to build their exoskeletons. It and barium have some uses in medicine, for example "barium meals" in radiographic imaging, whilst strontium compounds are employed in some toothpastes.
Beryllium and radium, however, are toxic. Beryllium's low aqueous solubility means it is rarely available to biological systems; it has no known role in living organisms, and when encountered by them, is usually highly toxic. Radium has a low availability and is highly radioactive, making it toxic to life.
Read more about this topic: Alkaline Earth Metal
Famous quotes containing the words biological, role and/or precautions:
“I am fifty-two years of age. I am a bishop in the Anglican Church, and a few people might be constrained to say that I was reasonably responsible. In the land of my birth I cannot vote, whereas a young person of eighteen can vote. And why? Because he or she possesses that wonderful biological attribute—a white skin.”
—Desmond Tutu (b. 1931)
“Mental health data from the 1950’s on middle-aged women showed them to be a particularly distressed group, vulnerable to depression and feelings of uselessness. This isn’t surprising. If society tells you that your main role is to be attractive to men and you are getting crow’s feet, and to be a mother to children and yours are leaving home, no wonder you are distressed.”
—Grace Baruch (20th century)
“A multitude of little superfluous precautions engender here a population of deputies and sub-officials, each of whom acquits himself with an air of importance and a rigorous precision, which seemed to say, though everything is done with much silence, “Make way, I am one of the members of the grand machine of state.””
—Marquis De Custine (1790–1857)