BIOLOGY
AMINO ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The zwitterion predominates at a lower pH.
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When an amino acid is dissolved in water, it existsin solution as the dipolar ion.
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The nonionic form occurs in significant amounts in aqueous solutions.
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A zwitterion can act as either an acid (proton acceptor), or a base (proton donor).
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Detailed explanation-1: -All the statements are correct.
Detailed explanation-2: -In water, the ionic attractions between the ions in the solid amino acid are replaced by strong attractions between polar water molecules and the zwitterions. This is much the same as any other ionic substance dissolving in water.
Detailed explanation-3: -In aqueous solution, an amino acid exists as a dipolar ion, which is known as Zwitter ion.
Detailed explanation-4: -Amino acids are colourless, crystalline solids. They are soluble in water and solubility varies with R-group of amino acid.
Detailed explanation-5: -An amino acid has both a basic amine group and an acidic carboxylic acid group. There is an internal transfer of a hydrogen ion from the-COOH group to the-NH2 group to leave an ion with both a negative charge and a positive charge. This is called a zwitterion.