Which of the following DNA molecules would be more stable un

Which of the following DNA molecules would be more stable under conditions of increasing temperature?

1)A DNA molecule that has more guanine and cytosine nucleotides

2) Both DNA molecules would be equally stable under conditions of increasing temperature

3) A DNA molecule that has more adenine and thymine nucleotides

Solution

Answer:

1)A DNA molecule that has more guanine and cytosine nucleotides

Explanation:

There are two hydrogen bonds between adenine and thymine (A=T) and three hydrogen bonds between cytosine and guanine (G=C). Thus the bond between cytosine and guanine (G=C) is more stable.