Answer:
False
Explanation:
Scientist believe that the primitive atmosphere lacked free oxygen. Oxygen is a highly reactive molecule that would have made difficult for complex macromolecules to appear and then create life.  Rocks from the precambrian period support this theory. 
Anaerobic cells appeared first, then photosynthesis appeared filling the atmosphere with oxygen and the aerobic organism develop cellular respiration to obtain energy, a process more efficient than anaerobic respiration.
 
        
             
        
        
        
Robert Hooke discovered cells by observing Cork with a homemade microscope.
        
                    
             
        
        
        
Answer:
C3 photosynthesis produces a three-carbon compound via the Calvin cycle while C4 photosynthesis makes an intermediate four-carbon compound that splits into a three-carbon compound for the Calvin cycle. Plants that use CAM photosynthesis gather sunlight during the day and fix carbon dioxide molecules at night.
Explanation: