hematopoiesis. (physiology). The process by which the cellular elements of the blood are formed.ematopoiesis. (physiology). The process by which the cellular elements of the blood are formed.
This is why Everest climbers typically make several trips up and down the mountain to increasingly high elevation camps to acclimate their bodies to high altitude conditions. Other risks to Everest climbers include frostbite and hypothermia from the extreme temperatures, thrombosis or embolisms caused by thickening of blood in response to high altitude, extreme sunburn, and broken bones from falls.
Lack of oxygen is one of the major challenges posed by Everest. The oxygen levels at the top are only a third of what they are at sea level. Humans cannot survive for any length of time at elevation above 26,000 feet (8000 m), which on Everest is known as the death zone.