Question

iv. There is less oxygen in the air at high altitudes than at sea level. Scientists have
shown that people living at sea level have about 5 million red blood cells per mm of
blood whereas people living at high altitude have 7 million red blood cells per mm3
of blood.
Suggest a reason for this difference.​

Answer 1

Number of red blood cells per unit volume of blood is likely to be higher in a person living at high altitudes. This is in response to the air being less dense at high altitude and number of red blood cells is needed to trap O2 from rarefied air having lowp O2 (partial pressure of oxygen).

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