A bacteria cell differs from a plant or animal cell by being less complex in structure.
        
             
        
        
        
Mitosis is the term i believe you're looking for
        
             
        
        
        
By using microscopes scientists were able to discover the existence of microorganisms, study the structure of cells, and see the smallest parts of plants, animals, and fungi.
        
             
        
        
        
They are buried in the core of the structure.
        
             
        
        
        
Cnidarians were the first phylum that scientists saw tissue level organization in. Tissue level organization meaning cells all of one type start to function in a unified way.