Question

The affinity of hemoglobin for oxygen changes as blood travels from the lungs to the body tissues and back to the lungs again. One could expect hemoglobin to have

• A. A high carbon dioxide affinity in the lungs and a low oxygen affinity in the tissues
• B. A low carbon dioxide affinity in the lungs and a high oxygen affinity in the tissues
• C. A high oxygen affinity in the lungs and a low oxygen affinity in the tissues
• D. A low oxygen affinity in the lungs and a high oxygen affinity in the tissues
• E. A high oxygen affinity in the lungs and a high carbon dioxide affinity in the lungs

Answer 1

The correct option is C A high oxygen affinity in the lungs and a low oxygen affinity in the tissues

Haemoglobin is protein pigment of red blood cells which is remarkably suited for transport of oxygen. It binds to oxygen under higher alveolar oxygen concentration and little higher pH and cooler temperature. The product is oxyhemoglobin. Likewise, under the lower concentration of oxygen in the tissues and comparatively lower pH and warmer temperature in the tissues facilitates the release of oxygen from hemoglobin and formation of deoxyhemoglobin (Hb).

Therefore, the correct answer is option C.