Amino acids are the monomer units of polymeric macromolecules called proteins. Amino acids are built upon chains of carbon atoms to which various groups such as hydroxyl (OH), double-bonded oxygen (O=), carboxyl (COOH), methyl (CH3) and amino (NH2) are attached. The appendages to the base carbon chain often consist of 5- or 6-member rings of carbon and nitrogen. The linear skeletons contain from one to five carbon atoms, and occasionally incorporate a sulphur atom. There are 20 amino acids, six of which are depicted in Fig. 11.1. The lines joining the atoms represent covalent single bonds, in which an electron from each atom is shared with the adjacent atom. The names of the amino acids are shown together with the number of carbon atoms in the basic skeleton (in parentheses). The various appendages are highlighted. Each species has a carboxyl group and an amino group at one end. An important property of the amino acids is the ease with which the terminal H on the carboxyl group can be transferred to the neighboring amino group, creating a dipole:
which enhances the solubility of the amino acid in water.
Reaction of the carboxyl group of one amino acid with an amino group of another results in a peptide bond.
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Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.