B) A node would be introduced.
This would be used to help provide distinctions to these species
 
        
                    
             
        
        
        
Answer:
Microvilli is very common in these cells. They increase the absorption area. 
Explanation:
Epithelial cell surfaces show different structure shapes that allow the cells to adapt to and accomplish their functions. Most of these structures are related to the absorption surface and the need to move substances.
The development of microvilli is very common in epithelial cells. These are folds or finger-like projections emerging from the apical surface of the cell. <u>Their principal function is to absorb</u>. The microvilli of the intestinal epithelium are very uniform in size and distribution. 
 
        
             
        
        
        
Answer:
(a). soft substrates
Explanation:
Mobile organisms can be measured by both direct and indirect methods. Direct methods may involve observing the actual behavior (e.g., scoring via timing). Moreover, indirect methods are those where the technique used depends on the species being examined, collecting information such as through recording of tracks in the soft substrate (e.g., mud, sand, snow), presence of fur/feathers, droppings (mammals), etc. For example, indirect observation of insects may involve the determination of exoskeletons, sounds, etc.
 
        
             
        
        
        
This process is called melting. When a solid melts, it turns into a liquid.