Answer:
A. At high altitude, increase in 2,3-bisphosphoglycerate (BPG) ensures that enough oxygen is delivered to the tissues despite the low oxygen saturation levels there.
B. An increase in 2,3-bisphosphoglycerate (BPG) is necessary during pregnancy as it ensures that both the pregnant woman and developing fetus have enough oxygen for their metabolic needs.
Step-by-step explanation:
Atmospheric pressure is low at high altitudes with the result that oxygen molecules in the air are further apart. The reduction of oxygen availability in the air thus reduces the oxygen saturation in the blood and brain. Oxygen saturation levels refer to the extent hemoglobin is bound or saturated to oxygen.
2,3-bisphosphoglycerate (BPG) is an allosteric inhibitor of oxygen binding to hemoglobin. At low concentration, oxygen delivery to tissues is low while at hgh concentrations, oxygen delivery to tissues increases. It ensures that oxygen bound to hemoglobin in blood from the lungs is delivered to the tissues. Thus, at high altitude, increase in BPG ensures that enough oxygen is delivered to the tissues despite the low oxygen saturation levels there.
B. During pregnancy, there is a significant increase in oxygen demand. This is due to a 15% increase in the metabolic rate and a 20% increased consumption of oxygen as the developing fetus obtains nutrients and oxygen from the mother's blood.
An increase in 2,3-bisphosphoglycerate (BPG) is necessary during pregnancy as it ensures that both the pregnant woman and developing fetus have enough oxygen for their metabolic needs.