Answer:
Cell respiration begins with Glycolysis
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Explanation:
Glycolysis  is the first and initial step in the cellular respiration. Cellular respiration is the anaerobic process, which takes place in cytosol of the cells. Two molecule of pyruvate(CH3COCOO-) are formed from 1 molecule  of  glucose(C6H12O6)through glycolysis. The  NADH and  ATP are high energy molecules formed when the free energy are released. It is the process which takes place through a series of ten enzyme catalysed reactions. 10 enzymes are required to break down the sugar molecule. It occurs in cytoplasm.
 
        
             
        
        
        
The lungs have no skeletal muscles of their own. The work of breathing is done by the diaphragm, the muscles between the ribs (intercostal muscles), the muscles in the neck, and the abdominal muscles.
        
                    
             
        
        
        
The nucleus intructs cells to do their activities