Four factors favourable for the formation of oxyhaemoglobin in alveoli
Answers
A sigmoid curve is obtained when percentage saturation of haemoglobin with O2 is plotted against the pO2. This curve is called the oxygen dissociation curve and is highly useful in studying the effect of factors like pCO2, H+ concentration, etc., on binding of O2 with haemoglobin. In the alveoli, where there is high pO2, low pCO2, lesser H+ concentration and lower temperature, the factors are all favourable for the formation of oxyhaemoglobin, whereas in the tissues, where low pO2, high pCO2, high H+ concentration and higher temperature exist, the conditions are favourable for dissociation of oxygen from the oxyhaemoglobin. This clearly indicates that O2 gets bound to haemoglobin in the lung surface and gets dissociated at the tissues. Every 100 mL of oxygenated blood can deliver around 5 mL of O2 to the tissues under normal physiological conditions.
Answer:
Following are the four factors that are responsible for the oxyhaemoglobin in alveoli:
Partial pressure of oxygen:
The greater the partial pressure of the oxygen causes the binding of hemoglobin with the oxygen efficiently.
Temperature:
The normal temperature favors the binding of hemoglobin with oxygen. The high temperature is responsible for the dissociation of the oxygen from haemoglobin.
Amount of carbon dioxide:
The large amount of the carbon dioxide decreases the formation of the oxyhaemoglobin. The carbon dioxide has more affinity for haemoglobin than with the oxygen.
Hydrogen ions:
The increase in the hydrogen ion concentration or decrease in pH causes the increases in the dissociation of haemoglobin.