When the concentration gradient of such molecules is high on the either the cytoplasmic side or the extracellular side of the cell. When the concentration gradient is high it flows freely through the cell membrane to the other side without expanding energy. 
Hope i helped!
        
             
        
        
        
If the warm air rises high enough, the air will eventually cool to its dew point. When it cools to its dew point, it begins the process of condensation. Starting from here, as air rises, the heat of condensation stored in water vapor will gradually release.
        
             
        
        
        
Will take place in the nucleus where the DNA is located
        
             
        
        
        
The
response is false. Evolutively, thought is the last to develop,
therefore, it is the most plausible element to be modified and, in
this process of change, emotions<span> will accompany.</span>