Search results
Results from the WOW.Com Content Network
Trace metals are the metals subset of trace elements; that is, metals normally present in small but measurable amounts in animal and plant cells and tissues. Some of these trace metals are a necessary part of nutrition and physiology. Some biometals are trace metals. Ingestion of, or exposure to, excessive quantities can be toxic.
A trace element is a chemical element of a minute quantity, a trace amount, especially used in referring to a micronutrient, [1] [2] but is also used to refer to minor elements in the composition of a rock, or other chemical substance. In nutrition, trace elements are classified into two groups: essential trace elements, and non-essential trace ...
The generally accepted trace elements are iron, chlorine, cobalt, copper, zinc, manganese, molybdenum, iodine, selenium, [5] and bromine; [6] there is some evidence that there may be more. The four organogenic elements, namely carbon, hydrogen, oxygen, and nitrogen , that comprise roughly 96% of the human body by weight, [7] are usually not ...
Not all elements which are found in the human body in trace quantities play a role in life. Some of these elements are thought to be simple common contaminants without function (examples: caesium, titanium), while many others are thought to be active toxins, depending on amount (cadmium, mercury, lead, radioactives).
In biochemistry, an ultratrace element is a chemical element that normally comprises less than one microgram per gram of a given organism (i.e. less than 0.0001% by weight), but which plays a significant role in its metabolism.
By definition, incompatible trace elements have an equilibrium constant value of less than one because trace elements have higher concentrations in the melt than solids. [1] This means that compatible elements have a value of >. Thus, incompatible elements are concentrated in the melt, whereas compatible elements tend to be concentrated in the ...
Metal ions are common cofactors. [11] The study of these cofactors falls under the area of bioinorganic chemistry. In nutrition, the list of essential trace elements reflects their role as cofactors. In humans this list commonly includes iron, magnesium, manganese, cobalt, copper, zinc, and molybdenum. [12]
Iron oxide copper-gold deposits are also often associated with other valuable trace elements such as uranium, bismuth and rare-earth metals, although these accessories are typically subordinate to copper and gold in economic terms. Some examples include the Olympic Dam, South Australia, and Candelaria, Chile deposits.