Answer:
It only allow certain material to enter the cell
 
        
             
        
        
        
Answer:
B.Hemogoblin
Explanation:
these are the cells cariesd by the molecule
 
        
                    
             
        
        
        
The overall mechanism of cellular respiration<span> involves four subdivisions: glycolysis, in which glucose molecules are broken down to form pyruvic acid molecules; the Krebs cycle, in which pyruvic acid is further broken down and the energy in its molecule is used to form high-energy compounds such as NADH.
Source: </span><span>Cellular Respiration - Cliffs Notes</span>
        
                    
             
        
        
        
The first known single-celled organisms appeared on Earth about 3.5 billion years ago, roughly a billion years after Earth formed. More complex forms of life took longer to evolve, with the first multicellular animals not appearing until about 600 million years ago.