Answer:
Thymine= 60 ng
Guanine= 20 ng
The complementary base pairing occurs between adenine and thymine and guanine and cytosine bases.
Explanation:
According to the Chargaff rule, a double-helical DNA molecule has an equal number or equal amount of adenine and thymine bases since adenine always pairs with thymine. Similarly, the amount of guanine base is equal to that of the cytosine base.
Chargaff rule is based on the complementary base pairing between purine and pyrimidine bases. According to the given information, the amount of adenine is 60 ng. Therefore, the cell would have 60 ng thymine. Similarly, the amount of the cytosine base in the cell is 20 ng which means that the cell would have 20 ng of guanine base.
Enzymes bind with chemical reactants called substrates
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