Answer:
pH - Each enzyme has an optimal pH at which it works best, if the pH is too acidic or basic, the enzyme will start to denature.
Temperature - Each enzyme has an optimal temperature at which it works best as well. If it is too hot, the enzyme will start to denature and if it is too cold, there will be fewer collisions between enzymes and substrates.  
Explanation:
 
        
             
        
        
        
Answer: Embryonic stem cells
Explanation: Cell differentiation is the process whereby an immature cell evolves to specialized form to perform its function. It take place in Embryonic stem cells. 
 
        
             
        
        
        
Answer:
Nitrogen fixation
Explanation:
Biological nitrogen fixation is carried out by two types of microorganisms namely, symbiotic and free living microorganisms. Symbiotic microorganisms are bacteria f the genus <em>Rhizobium</em>. These are found in root nodules of leguminous plants. They convert atmospheric nitrogen into ammonia which is used directly by leguminous plants to form nitrogen containing organic compounds.
 
        
             
        
        
        
Yes, when you see that plus sign on the top right corner of an element, it means it lost one electron, making the element a slightly more positive charge, (called a cation).
        
             
        
        
        
Aaugcg since it mRNA you replace t with u