The answer will be C decreases
        
             
        
        
        
Answer:
During photosynthesis the oxygen is released into the atmosphere through
All photosynthetic eukaryotic cells contain chloroplasts that use the radiant energy of sunlight to convert carbon dioxide and water into carbohydrates. As a byproduct of photosynthesis, oxygen gas is also released into the atmosphere through tiny openings in the leaves called stomata.
Explanation:
 
        
             
        
        
        
Answer:
The nitrogenous bases guanine and adenine are A. purines.
Explanation:
Adenine and guanine are purines, whereas the other two bases in DNA (thymine and cytosine) are pyrimidines.  The main difference between purines and pyrimidines is the number of rings that the base has: purines have two rings while pyrimidines only have one ring.  
In addition, phosphate group and sugar group cannot be the answer to this question because these two elements in addition to a nitrogenous base makes up a nucleotide.
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