Answer:
It is used by every living cell
Explanation:
 
        
                    
             
        
        
        
One Y and one X chromosome.
        
             
        
        
        
Do excrete all the toxins from our food and body, yes we need to pee.
        
                    
             
        
        
        
Well, the domain humans belong to (when I did a little research) is that they are actually a Eukaryote. Therefore, I'd say C, Eukarya. I hope this helps! ~Mia
        
                    
             
        
        
        
Answer:
Ecology is the study of how organisms interact with one another and with their physical environment.
Explanation: