Question
In $$DNA,$$ the complementary bases are
A.
adenine and thymine, guanine and cytosine
B.
uracil and adenine, cytosine and guanine
C.
adenine and guanine, thymine and cytosine
D.
adenine and thymine, guanine and uracil
Answer :
adenine and thymine, guanine and cytosine
Solution :
$$DNA$$ has a double helical structure. These helix contains polynucleotide chains and these chains are held together by hydrogen bonds. In these polynucleotide chain of $$DNA,$$ adenine has thymine opposite to it and guanine has cytosine opposite to it.