Answer:
A
Explanation:
It's basically doing by its own
 
        
                    
             
        
        
        
Proteins, Ribonucleic acid is another kind of organic molecule that also acts as a catalyst for chemical reactions. Asides acting a catalyst for chemical reactions, proteins have a wide variety of functions that they perform in in living cells.
        
             
        
        
        
The answer is that Both aid in the expansion and relaxation of lungs. Diaphragm and the rib muscles are vital in the breathing process. During inhalation the intercostal muscles contract, expanding the ribcage, the diaphragm contracts, pulling downwards to increase the volume of the chest, pressure inside the chest is lowered and air is sucked into the lungs. During exhalation the intercostal muscles relax, the ribcage drops inward and downwards, the diaphragm relaxes, moving back upwards, decreasing the volume of the chest, the pressure inside the chest increases and air is forced out. 
        
             
        
        
        
<span>Given that Jason, middle school boy, is well below normal height for his age, it is possible that Human Growth Hormone might be in short supply in his body. </span>Growth hormone<span> (h</span>GH<span>) is also called S</span>omatotropin. <span>This hormone is responsible for the </span><span>stimulation of growth, </span>cell<span> reproduction, and cell regeneration in humans.</span>