Soon the deoxygenated red blood cells are back in the lungs, where the hemoglobin molecules will release the carbon dioxide and be recharged with life - sustaining oxygen ​ — a process that is repeated many thousands of times during a red blood cell’s life span of about 120 days.
תהליך זה חוזר על עצמו אלפי פעמים במחזור חייו של תא דם אדום, הנמשך כ ־ 120 יום .‏