Question
Biology Question on Exchange Of Gases
The haemoglobin of a human foetus
A
has only 2 protein subunits instead of 4
B
has a higher affinity for oxygen that that of an adult
C
has a lower affinity for oxygen than that of the adult
D
its affinity for oxygen is the same as that of an adult.
Answer
has a higher affinity for oxygen that that of an adult
Explanation
Solution
Oxygen is needed for aerobic respiration and diffuses from a region of high to low concentration from the mother's blood to the blood of the foetus. The haemoglobin of the fetus has a higher affinity for oxygen than that of adult haemoglobin and so the efficiency of exchange is increased. Carbon dioxide, a waste product of aerobic respiration diffuses in the opposite direction.