The correct answer is that different genes are expressed in different cells.  
The cellular differentiation is the process in developmental biology where a cell modifies from one kind of cell to another. Most generally the cells are modified to a more specialized kind. Differentiation takes place various times at the time of development of a multicellular species as it modifies from a basic zygote to a composite system of tissues and kinds of cells.  
 
        
                    
             
        
        
        
Answer: Its when you don't know nothing and lose most of your cells and barely know aything p.s IGMME 
 
        
             
        
        
        
Answer:
46 chromosomes
Humans have 23 pairs of chromosomes, so our hearts have 46 chromosomes.
Explanation:
Hope it helps 
 
        
                    
             
        
        
        
Answer:
Theory
Explanation:
It is a substantiated explanation because of the set of facts and observations on the experiment. 
 
        
             
        
        
        
Answer:
adding chlorine, checking the water.
Explanation:
Because this increases the quality of the water while the rest improve either quantity, or ease of access.