It is a chemical process which enables heterotrophs to obtain energy without oxygen.
        
                    
             
        
        
        
Answer:
#19 = The cell is an animal cell because it's missing the organelles required in plant cells(chloroplast, vacuoles, and the cell wall) 
#20 = The mitochondria would be most likely to be affected because it's the powerhouse of the cell, provides energy, and imports proteins. I hope this helps.
Explanation:
 
        
             
        
        
        
DNA fragments are cut out restriction enzymes (restriction endonucleases) and then joined together using enzymes called DNA ligases.
<span>Restriction enzymes are enzymes which recognize target sequences (recognition sites) and cuts DNA at or near those sequences.</span>
DNA ligase is an enzyme that connects the gap between the molecules (if they have matching ends).
 
        
             
        
        
        
Its conversion of pyruvate, a process where each molecule loses one carbon atom with the release of carbon dioxide