What is the copper-transport plasma protein in the human body?

Ceruloplasmin is the primary copper-transport plasma protein in the human body. It plays a crucial role in transporting copper, an essential trace element, throughout the bloodstream. Copper is vital for numerous enzymatic reactions and physiological processes, including iron metabolism, as ceruloplasmin also has ferroxidase activity, converting ferrous iron (Fe2+) to ferric iron (Fe3+) for proper transport in conjunction with transferrin.

Furthermore, ceruloplasmin helps maintain copper in its oxidized form, ensuring its availability for necessary biological functions. The protein is synthesized in the liver, and low levels of ceruloplasmin can indicate conditions like Wilson's disease, where copper accumulates in tissues due to impaired excretion.

Other proteins mentioned, such as serum albumin, transferrin, and ferritin, have different functions. Serum albumin primarily carries various substances in the blood, including hormones, fatty acids, and drugs. Transferrin is specifically involved in transporting iron, not copper. Ferritin primarily serves as an intracellular protein for iron storage. Since ceruloplasmin uniquely fulfills the role of copper transport, it is the correct answer to this question.