Biologists assigned universally accepted names to organisms because t<span>hey needed to create a unique name that would be recognized as belonging to one organism.</span>
        
                    
             
        
        
        
Answer:
[The recent activities of fossil fuel combustion has had adverse effects on the ozone layer]- B.
 
        
                    
             
        
        
        
Humans can make a difference but carbon is everywhere. This generation has the largest carbon footprint yet.
        
             
        
        
        
Answer:
A frogs heart has 3 chambers. Two atria and a single ventricle. 
 
        
             
        
        
        
Answer:
B. retain its urine in it’s blood stream
Explanation:
Sharks are cartilaginous fishes that lives in the ocean. Oceans are always salty, hence organisms need to maintain a salt-water balance between their internal and external environment because of osmosis. Sharks are able to maintain this by ensuring that the amount of solutes in their internal environment is as much as that in their external environment.
Sharks retain a chemical contained in urine called UREA in their bloodstream to counter the osmotic effect of the salt concentration in the waters they live. This helps them maintain a concentration balance with their environment.