Copper is mainly transpoed by ?

Ans. is 'a' i.e., CeruloplasminCopper is mainly transpoed as ceruloplasmin :?Normally, 40% to 60% of daily ingested copper (2 to 5 mg) is absorbed in the stomach & duodenum. o It is transpoed to the liver loosely complexed with albumin.Free copper dissociates and is taken up into hepatocytes, where it is incorporated into an a,-globulin synthesized in the endoplasmic reticulum to form ceruloplasmin (a copper-containing metallothionein) and resecreted into plasma.Ceruloplasmin accounts for 90% to 95% of plasma copper, although its biologic role is unknown, since the six to seven atoms of copper in each protein molecule are not readily exchangeable.Circulating ceruloplasmin is desialylated as pa of normal plasma protein agingDesialylated ceruloplasmin is endocytosed by the liver, degraded within lysosomes, and its copper is excreted into bile. This degradation/excretion pathway is the primary route for copper elimination.Estimated total body copper is only 50 to 150 mg.