why must the bonds of these molecules be broken before anything else happens 
Explanation:
yan po
 
        
             
        
        
        
Go to the Prenatal Testing page for more details. If one parent has sickle cell trait (HbAS) and the other has sickle cell anaemia (HbSS) there is a one in two(50%) chance that any given child will get sickle cell trait and a one in two chance that any given child will get sickle cell anaemia.
        
             
        
        
        
At the very end of the cladogram at the very top of a clade in the middle of a clade along the main trunk of the cladogram