REGULATION OF IRON ABSORPTION
TRANSPORT TO BLOOD DEPENDENT ON BLOOD LEVELS
HYPOTHESIS: WHEN BLOOD LEVELS ARE HIGH, MORE FERRITIN IS FORMED --> MORE "TRAPPED" IN CELLS. IN IRON DEFICIENCY, MORE TRANSPORT PROTEIN IS SYNTHESIZED AND LESS FERRITIN.
IRON TRAPPED IN CELL BOUND TO FERRITIN IS LOST WHEN CELLS SLOUGH OFF AND DISINTEGRATE, SINCE IT CAN NOT GET INTO THE INTACT CELLS IN THIS FORM.