Bro if u dont know this answer you better pay attention in class cause this is the easiest thing i have ever seen. And if you cant find the answer in your class book come back in here and i will hook you up.<span />
        
             
        
        
        
They have the same mass as the mass of the reactants. evidence to back this up is the law of conservation of mass
        
                    
             
        
        
        
<u>Cell culture i</u>s the method applied by scientists to grown, cells in the laboratory setting to study the cells for particular reasons.
Explanation:
Cell culture is basically a method for survival, reproduction etc which are done under controlled conditions in the space outside the environment. This is also used for data mining.
 Purpose: Cell culture is used for propagation of virus 
Advantages:
- Vaccine production by replication of virus
- Detection of viral cell of virus
- Convenient easy and economical method
Disadvantages
- Maintenance of sterile aseptic conditions.  
- Increases microbial contamination
- Cross contamination takes place
 
        
             
        
        
        
D) Long chains of amino acids used for building, repair, and maintenance
Proteins are made up of amino acids, and they are used to create substances (like hair, nails, etc.)
Hope this helps!!