Its called osmosis and it only happens with water. now I'm just adding words to be able to post this. its moving down the concentration gradient.
        
             
        
        
        
It is a cold Artic air mass over Siberia. Air masses are altered because it doesn't stay in one place and changes as it moves due to the temperature of environment that can be caused by moisture. The cold Artic Mass from Siberia will go to the North Pole, Canada then moves further to the South area.
        
             
        
        
        
The answer would be genes.
        
             
        
        
        
Developing a coelom made nutrients more easily absorbed by roundworms. A coelom is a fluid filled cavity developed in the mesoderm and it is the main body of a roundworm. It contains the digestive tract and many other organs.