BIOLOGY
AMINO ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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leucine
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lysine
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histidine
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isoleucine
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Detailed explanation-1: -Threonine is an amino acid that is both glucogenic and ketogenic.
Detailed explanation-2: -Thus, leucine is ketogenic, and isoleucine and valine are ketogenic and glucogenic.
Detailed explanation-3: -In humans, two amino acids – leucine and lysine – are exclusively ketogenic. Five more are both ketogenic and glucogenic: phenylalanine, isoleucine, threonine, tryptophan and tyrosine.
Detailed explanation-4: -Amino acids that are both glucogenic and ketogenic (mnemonic “PITTT"): Phenylalanine. Isoleucine. Threonine.
Detailed explanation-5: -Isoleucine is an amino acid and belongs to the class which has hydrocarbon R-groups. The primary metabolic end products of leucine metabolism are acetyl-CoA and acetoacetate; consequently, it is one of the two exclusively ketogenic amino acids, with lysine being the other.