L-lysine is an essential amino acid and must be supplied in the diet. By comparison, the stereoisomer D-lysine is not biologically active. Why can your body only utilize one form?

A. Antibodies recognize the D form and destroy it before your body can use it for nutritional purposes.
B. Since the L form and D form are chiral molecules, they will bind together and inhibit utilization of the D form.
C. Enzymes can only recognize a single, specific stereoisomer.
D. Since the L form and D form are enantiomers, they will bind together and inhibit utilization of the D form.


Answer: C

Biology & Microbiology

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