"Obtain and use energy" is your answer :) 
 
        
                    
             
        
        
        
Answer:
The applications are:
Explanation:
1;To increase the number of cells in the body
2;To ensure that human being have the same number of chromosomes in each generation through meiosis
3;To ensure growing h and development in human body since it increases the number of cells in the body
 
        
             
        
        
        
Answer:
 hunger, thirst, sleepiness
 
        
                    
             
        
        
        
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T-g-t-c-g-g-c-a would be the complementary strand