GENERAL HISTOLOGY

Detailed explanation-1: -As blood cells mature, they move towards the central region of the bone marrow, where they exit through a dense network of capillaries (small blood vessels) and enter the bloodstream.

Detailed explanation-2: -Hemoglobin contains iron, which allows it to pick up oxygen from the air we breathe and deliver it everywhere in the body. You can think of hemoglobin as the iron ("heme"), oxygen transport protein, ("globin") found in red blood cells. It’s the hemoglobin that gives red blood cells their color, too.