Question

People living at sea level have around 5 million $RBCs/m{m}^3$ of blood whereas those living at an altitude of 5400 m have around 8 million. This is because

• A. There is more UV radiation which enhances RBCs production
• B. People eat more nutritive food which helps in formation of more RBCs
• C. People get pollution free air to breathe with more oxygen becoming available
• D. Atmospheric $O_2$ level is less so that more RBCs are needed to absorb the required amount of $O_2$ to survive.

Answer 1

The correct option is D Atmospheric $O_2$ level is less so that more RBCs are needed to absorb the required amount of $O_2$ to survive.

D. Atmospheric O2 level is less so that more RBCs are needed to absorb the required amount of O2 to survive. At an altitude of 5400 m, the concentration of atmospheric oxygen is very low. Hence, to fulfill the oxygen requirement of our body, more RBCs are needed.

So the correct answer is "Atmospheric O2 level is less so that more RBCs are needed to absorb the required amount of O2 to survive."