One hemoglobin molecule can carry how many oxygen molecules?

Ans. D 4O2 TRANSPORTTransport occurs via two processes:* Hemoglobin bound O2 (99%)* Dissolved O2 (1%)* 1 Hb can carry 4 oxygen molecules.* Molecule of oxygen bound to hemoglobin depends on saturation of Hb (SaO2 /SpO2 ) with oxygen. SaO2 depends on PaO2 CALCULATION OF HB-BOUND O2 In arterial bloodIn venous blood* 97% hemoglobin is saturated with oxygen, at PaO2 of 95 mm Hg.* With this saturation, 1 g of Hb, contains 1.34 mL of O2 .* Therefore 100 mL of blood contains 20.1 mL of oxygen (when normal Hb = 15 gm%)* When hemoglobin is 100% saturated with O2 , hemoglobin binds 1.39 mL O2 per gm of Hb * At PvO2 of 40 mm Hg, Hb is only 75% saturated (SO2 =75%).* Therefore, 100 mL of venous blood would carry 14.4 mL of O2