This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Heart, Circulation, and Blood, Subject name: Physiology
Which one of the following is not a transport or binding protein? 
Select and explain. 
A. Erythropoietin, B. Ceruloplasmin, C. Lactoferrin, D. Transferrin
A: Erythropoietin
Answer: A: Erythropoietin 
Explanation: Ans. is 'a' ie Erythropoietin (Ref: Harper, 26/e, p609, p620, p583, Ganong 22/e, p488)Erythropoietin is a plasma protein that acts as a hormone. It's the major regulator of human erythropoiesis.Other Options.Ceruloplasmin - transports copper.Transferrin - transports iron.Lactoferrin - binds iron.