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Parts-per-million cube of relative abundance by mass of elements in an average adult human body down to 1 ppm. About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium ...
The body is made up of approximate 1.5% calcium and this abundance is reflected in its lack of redox toxicity and its participation in the structure stability of membranes and other biomolecules. [6] Calcium plays a part in fertilization of an egg, controls several developmental process and may regulate cellular processes like metabolism or ...
The element is normally found in association with other base metals such as copper and lead in ores. [34] Zinc is a chalcophile, meaning the element is more likely to be found in minerals together with sulfur and other heavy chalcogens, rather than with the light chalcogen oxygen or with non-chalcogen electronegative elements such as the halogens.
Twenty chemical elements are known to be required to support human biochemical processes by serving structural and functional roles, and there is evidence for a few more. [1] [9] Oxygen, hydrogen, carbon and nitrogen are the most abundant elements in the body by weight and make up about 96% of the weight of a human body.
Copper in the body normally undergoes enterohepatic circulation (about 5 mg a day, vs. about 1 mg per day absorbed in the diet and excreted from the body), and the body is able to excrete some excess copper, if needed, via bile, which carries some copper out of the liver that is not then reabsorbed by the intestine.
Gallium does not occur as a free element in nature, but rather as gallium(III) compounds in trace amounts in zinc ores (such as sphalerite) and in bauxite. Elemental gallium is a liquid at temperatures greater than 29.76 °C (85.57 °F), and will melt in a person's hands at normal human body temperature of 37.0 °C (98.6 °F).
The human body tends to treat Rb + ions as if they were potassium ions, and therefore concentrates rubidium in the body's intracellular fluid (i.e., inside cells). [69] The ions are not particularly toxic; a 70 kg person contains on average 0.36 g of rubidium, and an increase in this value by 50 to 100 times did not show negative effects in ...
Because of its relative longevity, 226 Ra is the most common isotope of the element, making up about one part per trillion of the Earth's crust; essentially all natural radium is 226 Ra. [29] Thus, radium is found in tiny quantities in the uranium ore uraninite and various other uranium minerals, and in even tinier quantities in thorium minerals.