The amino acids Val, Leu, and Ile are all degraded outside the liver by an aminotransferase and an α-keto acid dehydrogenase complex. These amino acids can all be classified as:

Question

The amino acids Val, Leu, and Ile are all degraded outside the liver by an aminotransferase and an α-keto acid dehydrogenase complex.  These amino acids can all be classified as:

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11ecba2d_128c_ba5e_a3bf_5189b902d4d0_MD0008_00 Amino acids have three components: an amino group, a carboxyl group, and a side chain, which are each bonded to the same carbon atom (known as the α-carbon). The various amino acid structures differ only by the composition of the substituent side chains, which contain different functional groups that give amino acids specific characteristics. This permits classification of amino acids based on the different side-chain characteristics. Major classifications include charged (acidic or basic), hydrophobic (nonpolar), and hydrophilic (polar and charged). Some amino acids fall into more than one of these categories. Val, Leu, and Ile are the three-letter abbreviations for valine, leucine, and isoleucine, respectively. The side chains of these amino acids are similar in functionality. Each is a hydrocarbon chain of varying length with branching at some point in the side chain. Because the side chains of these amino acids are composed of nonpolar hydrocarbon chains, they can be classified as hydrophobic. (Choices A and B) Acidic and basic amino acids contain negatively and positively charged side chains, respectively, at physiological pH, and have a nonzero net charge. Valine, leucine, and isoleucine contain uncharged side chains, and have a net charge of zero at physiological pH. (Choice D) The side chains of valine, leucine, and isoleucine do not contain any polar functional groups. The hydrocarbon side chains are nonpolar, making these amino acids hydrophobic rather than hydrophilic. Educational objective: Amino acids are made up of an amino group, a carboxyl group, and a side chain, all bonded to the same carbon atom. The side chains contain different functional groups that give amino acids specific characteristics, which allow the classification of amino acids based on their properties. Four main classifications of amino acids include acidic, basic, hydrophilic, and hydrophobic.

The Amino Acids Val, Leu, and Ile Are All Degraded