In comparison they both show feeding relationship in an ecosystem.
In contrast, a food chain is a simple linear feeding relationship while a food web is a complex feeding relationship.
2) The arrows is to show the direction of the feeding relationship
        
             
        
        
        
Melanin provides pigmentation to the skin and it also provides UV ray protection (which is its role in the epidermis).  
        
             
        
        
        
Answer:
contain two sets of each of the 23 chromosome types
 
        
             
        
        
        
Answer:
burn up in Earth's atmosphere