In a chemical reaction, the atoms and molecules that interact with each other are called reactants. ... No new atoms are created, and no atoms are destroyed. In a chemical reaction, reactants contact each other, bonds between atoms in the reactants are broken, and atoms rearrange and form new bonds to make the products.
 
        
             
        
        
        
All organisms descended from a common ancestor
        
             
        
        
        
Answer: A mollusk accidentally imported from Europe. They clog pipes and water ways.
Explanation:
 
        
                    
             
        
        
        
Answer:
atomic orbitals or subshells it the same name
 
        
             
        
        
        
Answer:The first one
Explanation:Parasites increase in the host's body because they need to reproduce, causing the number of parasites to increase