Proteins are made from long chains of smaller molecules called amino acids. These long chains are folded into particular shapes. This is important in relation to how antibodies and enzymes work. Enzymes are biological catalysts. There are optimum temperatures and pH values at which their activity is greatest.
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The words were not clear and crisp, but it was the end of the telegraph and the beginning of the telephone. The first long distance call occurred in 1892 when Bell called Chicago from New York. The price for a long distance call was $9 for the first five minutes. Bell did not stop with the telephone.