Peptide formation and protein synthesis

A simple amino acid in acid solution, NH2CH2COOH 

The charged amino acid molecules make excellent controllers of the acidity of an environment, in cells, and in body fluids, including in the stomach, as they can soak up excess acid or alkali. The protein structures on the lining of the stomach help to stabilize the acidity in it and to control the pH. These pH values can often be disturbed by over-eating or -drinking. 

Such compounds are called buffers which are discussed in more detail in Chapter 9. 

The CO-NH group is called a peptide group or peptide link . When many of these groups join together to form one big molecule it is called a polypeptide or protein molecule. 

Amino acids are invaluable because they can form long-chain polymers needed by our bodies in definite and prescribed patterns as determined by the cells. There are sometimes hundreds of amino acid units in these chains. There are special parts within the cells which synthesize the specialized proteins required from the small 

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