In copper deficiency, why does iron transport for heme synthesis fall?

1. Copper is a component of two plasma proteins, hephaestin and ceruloplasmin. 2. Both enable the oxidation of iron from its ferrous to its ferric form. 3. Only the oxidised form can bind to transferrin, the transport protein that carries iron to body cells. 4. Without copper that oxidation step fails, so transport of iron for heme synthesis decreases. 5. The iron does not disappear; it accumulates in tissues, where it can eventually cause organ damage. 6. Albumin is not the iron carrier, transferrin is, so that option names the wrong protein. 7. Storage as ferritin and recycling from dying erythrocytes both continue, so the block is specifically at the transport step. _Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 18 "The Cardiovascular System: Blood", section 18.3 Erythrocytes_