Two main factors that must be taken in consideration are temperature and the pH level.
The temperature shouldn’t be too low as it slows down the rate of reaction, meaning that the enzyme will work slower, but also not too high as it will cause the enzyme to denature (stops working as it should). 
The pH level is pretty much the same, shouldn’t be not too low nor too high.
        
             
        
        
        
Hyperkalemia, depolarization 
Hope this helps.
        
             
        
        
        
I believe you mean mid-ocean ridge?
If so, true. 
A mid-ocean ridge or mid-oceanic ridge is an underwater mountain range, formed by plate tectonics.
This uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary. 
A mid-ocean ridge demarcates the boundary between two tectonic plates, and consequently is termed a divergent plate boundary.
  
        
                    
             
        
        
        
All DNA is a cell is harbored in the nucleus, so DNA replication should only occur in the nucleus of the cell.
 
        
             
        
        
        
Possession of flagellum is not a taxonomic feature. many different unrelated organisms have flagellum. euglena, zooflagellates but also some fungi or even human sperm cells.