All of the following functions requires Zinc as a micro-element, EXCEPT:

Note: Zinc is absolutely required for normal spermatogenesis, fetal growth, and embryonic development. Zinc is also an integral component of many metalloenzymes. It is involved in the synthesis and stabilization of proteins, DNA, and RNA and plays a structural role in ribosomes and membranes. Copper plays an impoant role in iron metabolism, melanin synthesis, energy production, neurotransmitter synthesis, CNS function, the synthesis and cross-linking of elastin and collagen and the scavenging of superoxide radicals Ref: Russell R.M., Suter P.M. (2012). Chapter 74. Vitamin and Trace Mineral Deficiency and Excess. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.