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Q.
Molecular weight is highest of
UP CPMTUP CPMT 2013
Solution:
Guanine has the molecular formula $C_5H_5$ $N_5O$ with molecular weight of $151\, amu$. Adenine is $C_5H_5N_5$ (molecular weight $135\, amu$), cytosine is $C_4H_5N_3O$ (molecular weight $111\, amu$) and thymine is $C_5H_6N_2O_2$ (molecular weight $126\, amu$). Thus guanine is the heaviest nitrogenous base found in $DNA$.