So the important factors are air pressure, temperature, and humidity. The base it is normal and easy to breathe. As you go towards the summit the temperature drops, air density and pressure is low; air is thin, and the humidity is also low. This results in hyperventilation as the air pressure is low. Also there is a chance of getting Hypoxia. The environment is harsh.
B
digestive system absorbs water and nutrients and circulatory systems carries nutrients to cells and excretory system helps eliminate waste