Answer:
Pluripotent cells can be almost anything they want to be while totipotent are for ex, like zygotes. They can give rise to placenta and embryo
 
        
                    
             
        
        
        
Regulating pollutant discharges into the waters of the United States
        
                    
             
        
        
        
Answer:
1
Explanation:
Mostly because it was the BIGGEST thing that really happend during said event. The others happend yes but not as majorly as number 1.
 
        
             
        
        
        
They might go extinct if they can't keep up with the competition