Question

If a person, living at sea level, migrate to about $8000$ feet high hill, his blood after about fifteen days will mainly

Answer 1

• Physiological changes at higher altitude
• At higher altitude the supply of oxygen to the body tissues is deprived.
• The blood lacks proper supply of oxygen and this decreased oxygen content in the blood is detected by the kidneys.
• The interstitial fibroblasts of the kidney produce the hormone called erythropoietin in response to the low oxygen in the blood.
• This hormone stimulates the haematopoietic stem cells (in the bone marrow) to increase the proliferation and differentiation of RBCs and thus resulting in the increase in the haemoglobin.
• Hence, at higher altitude because of low oxygen content in the atmosphere, there is an increase in the number of RBCs and haemoglobin.
• Hence, option D is correct.