Process resulting from random motion of molecules by which there is a net flow of matter from a region of high concentration to a region of low concentration.
        
             
        
        
        
Answer:
pretty sure it is non contact forces
Explanation:
no touchy-touchy involved so yeah
 
        
                    
             
        
        
        
The integumentary system has a variety of functions; it may serve to waterproof, cushion, and protect the deeper tissues, excrete wastes, and regulate temperature, and is the attachment site for sensory receptors to detect pain, sensation, pressure, and temperature.
 
        
                    
             
        
        
        
The resin why our brain changes throughout our life time as human beings, is simply because of age. Whatever you might learn, or adapt to it will all effect the brain. Everything you do is what your brain makes you do, and it changes with everything you do it all has a huge impact on your brain. Everything, its all about age and time. Hope this was helpful !!