OBJECTIVE LIFE SCIENCE
BIOCHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Most of the carboxyl groups are dissociated and most of the amino groups bind O2
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Most of the carboxyl groups are dissociated
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Most of the carboxyl groups are dissociated create anion NH3-
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Most of the carboxyl groups are dissociated, create anion COO-and most of the amino groups bind H+ creating cation-NH3+
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Detailed explanation-1: -Thus when the pH is maintained at 7, carboxylic acids are ionized. In the same way, when an amine (typical ammonium ion pKa 10) is dissolved in water which is held at pH = 7, the water is the stronger acid so the amine is protonated to make the weaker acid.
Detailed explanation-2: -At pH 7.4, acidic amino acids like aspartate and glutamate will have a net negative charge. This is because the acidic groups in their side chains are deprotonated and have negative charged.
Detailed explanation-3: -At high pH, both the carboxyl and amine groups are deprotonated. At these pH values, the amino acid carries a net negative charge, and is dibasic.
Detailed explanation-4: -Answer and Explanation: Increasing the pH of a solution may cause the carboxyl group and amino group on an amino acid to deprotonate (i.e., lose a proton or ionize). The carboxyl groups ionize at acidic pH values, such as 2 or 3, while the amino groups will ionize at more alkaline pH values, such as 9 or 10.