Class 12th Biology 2011 Set1 Delhi Board Paper Solution
Question 21
The base sequence in one of the strands of DNA is TAGCATGAT.
The base sequence in one of the strands of DNA is TAGCATGAT.
a. Give the base sequence of its complementary strand.
b. How are these base pairs held together in a DNA molecule?
c. Explain the base complementarity rules. Name the scientist who framed this rule.
Answer
a. Complementary sequence is ATCGTACTA
b. The base pairs are held together by hydrogen bonds. Number of bonds may be double or triple.
c. Complementary rule says that adenine pairs only with thymine and guanine pairs only with cytosine with the help of double and triple hydrogen bonds respectively.
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