Answer:
D
Explanation:
We can’t use nitrogen from the air and that’s why we have to use bacteria to into something that we can use 
 
        
                    
             
        
        
        
I Think The answer is d I hope it helps just Trying To help others That I can
        
             
        
        
        
Infected cells create and release small proteins known as interferons, which help the immune system fight viruses. Interferons stop viruses from replicating by interfering with their ability to multiply within infected cells.
        
             
        
        
        
Answer:
damaged cells proliferate until the wounds heals
 
        
             
        
        
        
Our skin cells divide rapidly in order to maintain a protective barrier against infection.The outer skin layer is called the epidermis and contains mostly dead cells that contain keratin.Keratin is a tough fibrous protein found in hair,skin and calluses and acts as a protective coating.The epidermis cells are constantly undergoing mitosis so the outer dead cells containing keratin are rapidly replaced as they fall off, which occurs after so many days.Then the newer living cells start producing keratin,lose their cellular contents,then die and the cycle goes on.The skin acts as a barrier to infection,therefore,it's constantly renewed and repaired.