Indicate true (T) and false (F) statements below regarding erythropoiesis. Your answer would be a four-letter string composed of letters T and F only, e.g. TTTF.
( ) Oxygen stimulates the secretion of erythropoietin.
( ) Each human erythrocyte lives for a few days on average.
( ) All erythrocytes express "DON'T EAT ME" signals on their surface to prevent phagocytosis.
( ) It only takes 1 to 2 days for erythrocyte numbers to rise following stimulation with erythropoietin.