Because cell is composed of organelle and several little material which haven't an ability to increase in size just in same manner as a rubber therefore cell divide for increase their number .
i hope this is helpful
        
             
        
        
        
The place where an organism lives
        
                    
             
        
        
        
Answer:
ok so i think the X shape is a chromosome, that blank space in the big spot is calleed a nucleas. The arrow on the top right is a cell, the bottom right is base pair, the bottom left is dna and the top middle is called the gene.
Explanation:
 
        
             
        
        
        
Radius temperature and brightness