Answer:
They are veins and arteries. The primary function of arteries is to transport highly oxygenated, nutrient-rich blood from our hearts and distribute it to the rest of our body. Veins, on the other hand, are used to pump much-needed blood back to the heart.
 
        
                    
             
        
        
        
Atoms come together to form molecules because of their electrons. Electrons can join (or bond) atoms together in two main ways. When two atoms share electrons between them, they are locked together (bonded) by that sharing. These are called covalent bonds
 
        
                    
             
        
        
        
Your teeth brake down down large food particles by chewing or grinding.
        
             
        
        
        
Answer:
ocean water evaporates and becomes water vapor, then when the droplets grow larger they fall as precipitation
Explanation:
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Explanation:
Biologists attempt to answer questions about the living world.