Chirality is a characteristic of two similar things which cannot be superimposed on each other to form identical copies. The famous example is the left hand and the right hand. No matter how they are rotated, they remain distinct. They act differently, too (try to shake hands with someone with your left hand!). Chirality is normally seen in structures with non-super-imposable mirror images.
In chemistry, chirality normally involves molecules, which can be referred to as “right-handed” or “left-handed” molecules. In molecules, chirality is most often associated with an asymmetric carbon atom, though chirality can be found in molecules with no carbon atoms at all.
Chirality is a quality that can be found in chemistry, physics, mathematics (including knot theory), electromagnetism, and is the title of a manga series of comic books.
Chirality raises particular concerns and enigmas in chemistry, biology and pharmaceutical products. Thalidomide, for example, was a drug administered to reduce the pain and anxiety of pregnancy. The problem is that the drug was chiral; one “hand” was a sedative and the the “hand” created horrible birth defects. Thalidomide was sold as a 50/50 mix of these two chiral forms.
Chirality provides us with an enormous and unresolved mystery in the field of biology and organic chemistry. There are mirror image amino acids, L-amino-acids and D-amino-acids Human proteins are built exclusively from L-amino-acids Throughout life on earth, most amino-acids are the L form and most sugars are the D form. There are several theories attempting to explain why certain chirality is preferred by amino-acids and another by sugars; the “natural auto-amplification process” explanation has been linked to the second law of thermodynamics, perhaps the most widely accepted current explanation.
Chirality also exists in inorganic chemistry.
Chirality demonstrates that there is more to chemistry than the formula of the molecule, as important as that is.
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– this blog entry was assembled by the author mostly from http://en.wikipedia.org/wiki/Chirality_(chemistry) and
– this blog entry was assembled by the author mostly from http://en.wikipedia.org/wiki/Chirality_(chemistry) and
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