Amino acids are the monomers that makeup proteins. This amino acid is unionized, but if it were placed in water at pH 7, its amino group would pick up another hydrogen and a positive charge, and the hydroxyl in its carboxyl group would lose and hydrogen and gain a negative charge.
Explanation:
Each amino acid has the same fundamental structure, which consists of a central carbon atom, also known as the alpha (α) carbon, bonded to an amino group (NH2), a carboxyl group (COOH), and to a hydrogen atom. In the aqueous environment of the cell, both the amino group and the carboxyl group are ionized under physiological conditions, and so have the structures -NH3+ and -COO–, respectively. Every amino acid also has another atom or group of atoms bonded to the central atom known as the R group. This R group, or side chain, gives each amino acid protein-specific characteristics, including size, polarity, and pH.
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