The subunits of proteins are called  amino acids. Amino acid molecules are smaller than protein  molecules and are inside of the protein molecules.        Aminâ¦o acids are joined together by peptide bonds where the -COOH  group and the -NH2 group of two consecutive amino acids bond with  the loss of a water molecule.
How Much Does USPS Certified Mail Cost for 2017 The cost for sending by Certified Mail is $3.35. This was the amount set on January 22, 2017 by the post office. Five cents over the rate set in 2016. Certified is a fee that is independent of mailing or postage, And if the sender chooses to mail with an accompanying paper Return Receipt, a $2.75 fee applies (up $.05 over 2016). For an electronic receipt, just over half that much at $1.45.
The certified mail fee is $2.95 in addition to postage. For example, to mail a one-ounce letter by certified mail with no return receipt, the price is $.45 for postage plus $2â¦.95 for the certified mail fee for a total of $3.40. A return receipt costs extra. For more information about rates, see the Sources and related links section, below.