The lower boundary of the exosphere is called the exobase. It is also called exopause and 'critical altitude' as this is the altitude where barometric conditions no longer apply. Atmospheric temperature becomes nearly a constant above this altitude.
Sodium â the volatility and solvent mineral: essential to life, all body fluids contain sodium â itâs needed for many biochemical processes including water balance regulation, fluid distribution on either side of the cell walls, muscle contraction and expansion, nerve stimulation and acid-alkaline balance.
Sodium is one of the most important minerals in the body. The kidneys use sodium to maintain the proper balance of water and electrolytesâchemical substances such as sodium and potassiumâand sodium is critical for water retention. But this very characteristic can cause problems with blood pressure.