how do the red blood cells transport oxygen throughout the body?

Question

my science class wants to know how do the red blood cells do it.(as in transport oxygen.
thankies~

Answer 1

"Candyjac" has it correct. To add a few details. Red blood cells are simply bags of hemoglobin - a protein molecule containing four "heme" groups with Fe (iron) at the core. These bind oxygen molecules picked up from the lungs and release them to the cells of the body after being transported thought the circulation. Each red blood cell contains about 270 million hemoglobin molecules. Adults have roughly 20 to 30 trillion red blood cells. We make about 2 million every minute in the bone marrow. These cells have no nucleus, so they last only about 120 days. That is why they are constantly being replaced.
MD - hematologist

Answer 2

When you inhale, air enters your lungs. The lungs have a dense system of blood vessels, which are permeable to oxygen. Hemoglobin, a certain protein present in red blood cells, bind to the oxygen, and the blood carries it throughout the body, releasing oxygen to the tissues. Eventually the blood will cycle back to the lungs again, where this cycle will repeat.

Hope this helps.

Answer 3

RBCs have hemoglobin(Hb) which takes up O2. The Hb of arterial blood is 97% saturated with O2 & the Partial presure (Po2) is 95mmHg. the PO2 in the tissues is 40mmHg.This 55mmHg difference causes the diffusion of O2 from the blood to the tissues @ the capillaries. With the dissociation of O2 from the arterial blood, the venous blood gets to have a PO2 of 40mmHg. As this venous blood passes through the lungs, there again occurs diffusion of O2 from the alveoli into the RBCs, since the PO2 of alveoli is 104mmHg.With a PO2 of atmosphere @153mmHg, diffusion from atmosphere to the alveoli occurs.

Diffusion- movement from higher to lower concentration, downhill movement.
Partial pressure- Pressure exerted by O2 alone.