[Answer] Why is it difficult to breathe at high altitudes?

Answer: because atmospheric gases become thinner the higher you go

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Why is it difficult to breathe at high altitudes? High Altitude Breathing Technique | Livestrong.com Why is it hard to breathe at high altitude? | AnswersDrive Preparing for High Altitude Travel with COPD Why do you feel so awful at high altitudes? | Scienceline Breathing at high altitudes:-. Unlike breathing at sea level when we breathe at some place with high altitude the air pressure is comparatively low and even much lower at some such places. The air thus faces difficulty in reaching our body system and there is always a fear of death because of Asphyxia which is another name of death because of suffocation . When we breathe in air at sea level the atmospheric pressure of about 14.7 pounds per square inch (1.04 kg. per cm. 2 ) causes oxygen to easily pass through selectively permeable lung membranes into the blood. At high altitudes the lower air pressure makes it more difficult for oxygen to enter our vascular systems . ...

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